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Declining Balance Depreciation Calculator UK 2026 | Reducing Balance, Double Declining & Schedule
📉 Reducing Balance · Double Declining · Variable Rate · Full Schedule — Updated 2026

Declining Balance
Depreciation Calculator UK

Calculate reducing balance (declining balance) depreciation for any UK business asset. Choose from standard reducing balance, double declining balance, or custom variable rates — with a full year-by-year schedule showing net book value, annual charge, accumulated depreciation and monthly cost. Updated for UK GAAP FRS 102 and HMRC 2026.

3
Calculation Methods
50yr
Max Projection Period
FRS 102
UK GAAP Compliant
Free
No Sign-Up Required
⚠️ Important: Declining balance depreciation is used for financial accounting purposes under UK GAAP (FRS 102) only. It is disallowed for UK tax purposes — HMRC uses its own capital allowance system (AIA, Full Expensing, WDA) instead. See our HMRC Capital Allowances Calculator UK for the tax-relief calculation.

📋 In This Page

  1. Declining Balance Depreciation Calculator
  2. What Is Declining Balance Depreciation?
  3. The Reducing Balance Formula
  4. Double Declining Balance Method
  5. Worked Examples with Full Schedules
  6. Declining Balance vs Straight-Line
  7. Common UK Depreciation Rates by Asset Type
  8. Frequently Asked Questions

Declining Balance Depreciation Calculator UK

Four calculator modes — standard reducing balance, double declining balance, variable rate by year, and a batch asset comparison tool. Each generates a full depreciation schedule.

✅ Reducing Balance (Standard): Applies a fixed annual % to the asset's net book value each year. Produces higher charges in early years tapering over time. The most widely used declining balance method in UK business accounts under FRS 102.
Total purchase cost including delivery and installation (ex-VAT if VAT registered)
Common UK rates: Computers 33%, Vehicles 20–25%, Machinery 15–25%, Fixtures 10–15%
Estimated value at end of useful life. Set to 0 if none. Depreciation stops when NBV reaches residual.
✅ Double Declining Balance (DDB): Applies twice the straight-line rate to the net book value each year. The most aggressive front-loaded depreciation method. The rate is automatically calculated from the asset's useful life — you only need to enter the asset cost and useful life. DDB never fully reduces the asset to zero — when the straight-line charge becomes larger, a switch is typically applied.
Total purchase cost of the asset
Estimated number of years the asset will be used. The DDB rate = 2 ÷ Useful Life.
Depreciation stops when NBV reaches this amount. Set to 0 for no floor.
Standard DDB uses factor 2 (200% of straight-line rate)
✅ Variable Rate: Apply a different declining balance rate for each year — ideal for assets where the rate of value loss changes over the ownership period. Useful for car depreciation (higher in Year 1) or technology assets with rapidly changing obsolescence rates. Enter up to 10 custom annual rates.

Annual Depreciation Rates (%) — Enter a rate for each year:

Leave unused years blank. Depreciation stops when NBV reaches residual value or all rates are used.

📊 Method Comparison: Enter one asset and compare straight-line vs reducing balance vs double declining balance side by side. Shows net book value at each year end for all three methods simultaneously — useful for choosing the most appropriate policy for your accounts.
Used for straight-line calculation and as the DDB base
The fixed % rate for the standard reducing balance method

What Is Declining Balance Depreciation?

The declining balance method — also called the reducing balance method in the UK — is a depreciation technique that applies a fixed percentage rate to the asset's net book value (NBV) each year. Because the NBV falls each year, the pound amount of the depreciation charge also falls each year, even though the percentage rate stays the same. This produces a front-loaded depreciation profile — higher charges in early years and lower charges as the asset ages.

This pattern closely matches the real-world behaviour of most business assets. A delivery van loses more of its value in year one than in year five. A computer becomes obsolete rapidly in its first years but retains a small residual value for longer. For these reasons, the reducing balance method is often considered more economically realistic than straight-line depreciation, which charges the same amount every year regardless of actual value loss.

Under UK GAAP (FRS 102), businesses must select a depreciation method that best reflects the pattern in which the asset's economic benefits are consumed. The reducing balance method is expressly permitted and widely used for plant and machinery, motor vehicles, computers and most other depreciating business assets. The chosen method must be applied consistently year on year for each asset category unless there is a justified reason to change it.

💡 UK terminology note: In the UK, this method is most commonly called the reducing balance method. In US accounting it is called the declining balance method or double declining balance (DDB). They are all variations of the same mathematical approach — applying a percentage to the remaining book value rather than the original cost.

The Reducing Balance Depreciation Formula

The core formula is straightforward — you simply multiply the current net book value by the chosen annual depreciation rate. The result is that year's depreciation charge, which is deducted to produce the closing net book value carried forward to the next year.

🔢 Core Formula — Annual Depreciation Charge
Depreciation (Year N) = Opening Net Book Value × Depreciation Rate

Where: Opening Net Book Value = Asset Cost − Accumulated Depreciation to date.

🔢 Closing Net Book Value (End of Each Year)
Closing NBV = Opening NBV × (1 − Depreciation Rate)

This is the carrying amount on the balance sheet at year end. Repeat using the new NBV as the opening value for next year.

🔢 Shortcut — Net Book Value at Any Future Year
NBV at Year N = Original Cost × (1 − Rate) ^ N

The ^ symbol means "to the power of". Example: £75,000 × (1 − 0.20)³ = £75,000 × 0.512 = £38,400 at Year 3.

🔢 With Residual Value
Depreciation = (Net Book Value − Residual Value) × Depreciation Rate

When a residual (scrap) value is expected, only depreciate the amount above the floor. Depreciation stops once NBV reaches the residual value.

How to Find the Right Depreciation Rate

The depreciation rate should reflect how quickly the asset loses value in practice. For accounting purposes, the rate is a management estimate — not a fixed rule. Common UK approaches include:

  • Industry benchmarks — see the table in the UK Rates section below
  • Manufacturer guidance — some assets come with estimated useful life data
  • Historical experience — comparing past disposal proceeds to book values
  • HMRC rates as a proxy — 14% main pool WDA or 6% special rate pool are widely adopted as practical starting points
💡 UK GAAP FRS 102: The depreciation rate must reflect "the pattern in which the asset's future economic benefits are expected to be consumed." Once chosen, it must be applied consistently unless there is evidence the consumption pattern has changed — in which case it is treated as a change in accounting estimate and prospectively adjusted.

Double Declining Balance Method (DDB)

The double declining balance (DDB) method is the most widely known variant of declining balance depreciation. It automatically sets the depreciation rate at twice the straight-line rate based on the asset's useful life — producing the most aggressive front-loading of depreciation charges. The method is more common in US GAAP contexts but is also used under UK GAAP where a front-loaded pattern is most economically appropriate.

🔢 Step 1 — Calculate the Straight-Line Rate
Straight-Line Rate = 100% ÷ Useful Life (Years)

Example: an asset with a 10-year useful life has a straight-line rate of 100% ÷ 10 = 10% per year.

🔢 Step 2 — Double the Rate
DDB Rate = 2 × Straight-Line Rate

Example: 2 × 10% = 20% DDB rate. For a 5-year asset: straight-line = 20%, DDB = 40%.

🔢 Step 3 — Apply to Net Book Value Each Year
Annual Depreciation = DDB Rate × Net Book Value at Start of Year

Important: DDB never naturally reaches zero — when the annual DDB charge falls below the straight-line equivalent for the remaining balance, many businesses switch to straight-line for the remaining years to fully write off the asset by end of useful life.

Worked Example — Double Declining Balance

Worked Example

Factory Machine — Cost £50,000, Useful Life 5 Years, No Residual Value

Original Cost£50,000
Useful Life5 years
Straight-Line Rate100% ÷ 5 = 20%
DDB Rate (2×)2 × 20% = 40%
Year 1: £50,000 × 40%£20,000 dep → NBV £30,000
Year 2: £30,000 × 40%£12,000 dep → NBV £18,000
Year 3: £18,000 × 40%£7,200 dep → NBV £10,800
Year 4: £10,800 × 40%£4,320 dep → NBV £6,480
Year 5: £6,480 × 40%£2,592 dep → NBV £3,888
⚠️ After 5 years, NBV is still £3,888 — DDB has not fully written off the asset. A switch to straight-line in Year 4 or 5 would complete the write-off. Use our calculator above to see the full schedule with any switch option.

Worked Examples — Full Depreciation Schedules

Example 1 — Delivery Van (20% Reducing Balance)

Worked Example 1

XYZ Limited — Ford Transit Van, Cost £75,000, 20% Reducing Balance, No Residual

YearOpening NBVDep (20%)Accum. Dep.Closing NBVMonthly Charge
2026£75,000£15,000£15,000£60,000£1,250
2027£60,000£12,000£27,000£48,000£1,000
2028£48,000£9,600£36,600£38,400£800
2029£38,400£7,680£44,280£30,720£640
2030£30,720£6,144£50,424£24,576£512
Total (5 yrs)—£50,424—£24,576—
✅ After 5 years the van has a net book value of £24,576 — retaining 32.8% of its original cost on the balance sheet. Total P&L charge over 5 years: £50,424.

Example 2 — Computer Equipment (33% Reducing Balance)

Worked Example 2

Office Computer Setup — Cost £1,000, 20% Reducing Balance (FRS 102 illustration)

YearAsset Value (Opening)RateDepreciationAccum. Dep.
1£1,00020%£200£200
2£80020%£160£360
3£64020%£128£488
4£51220%£102.40£590.40
Total——£590.40£590.40
✅ After 4 years, £590.40 has been charged to P&L and the asset has a closing NBV of £409.60. This mirrors standard UK GAAP practice for computer hardware under FRS 102.

Declining Balance vs Straight-Line Depreciation

These two methods produce very different depreciation profiles over the same asset life. The right choice depends on the nature of the asset and how its economic benefits are consumed over time.

Feature Declining Balance (Reducing) Straight-Line
Annual charge pattern Higher in early years, lower later Equal every year
Formula Opening NBV × Rate % (Cost − Residual) ÷ Useful Life
Reaches zero? Mathematically never (without switch) Yes — at end of useful life
P&L impact in early years Higher charge = lower early profits Equal charge = smoother profits
Most realistic for Vehicles, computers, plant, machinery Buildings, fixtures, long-life assets
UK GAAP (FRS 102) allowed? ✅ Yes ✅ Yes
Allowed for UK tax (HMRC)? ❌ No — add back on CT600/SA ❌ No — add back on CT600/SA
Complexity Slightly more complex (recalculate NBV each year) Simplest method
Best used for Assets with heavy early-year use or obsolescence Assets consumed evenly over time

Numerical Comparison — Same Asset, Both Methods

Asset: £20,000 plant and machinery, 25% reducing balance vs straight-line over 5 years (residual £0):

YearReducing Balance (25%) Dep.RB Closing NBVStraight-Line Dep.SL Closing NBV
Year 1£5,000£15,000£4,000£16,000
Year 2£3,750£11,250£4,000£12,000
Year 3£2,813£8,437£4,000£8,000
Year 4£2,109£6,328£4,000£4,000
Year 5£1,582£4,746£4,000£0
Total Charged£15,254£4,746 remaining£20,000£0 remaining
💡 Key insight: Straight-line fully writes off the asset in 5 years. Reducing balance leaves a remaining NBV of £4,746 — the asset never mathematically reaches zero. For assets with genuine residual value, this is appropriate. For assets with no residual value, businesses often write off the remaining balance in the final year or switch to straight-line in later years.

Common UK Reducing Balance Depreciation Rates by Asset Type (2026)

These are commonly used reducing balance rates for UK businesses under FRS 102. They are not legally fixed — management must choose rates that best reflect actual value consumption. However, these benchmarks represent standard UK practice.

Asset TypeTypical RateUseful Life Equiv.Notes
Computers, Laptops, Tablets33%3–4 yearsHigh obsolescence rate — aggressive depreciation appropriate
Company Cars / Vans20–25%4–5 yearsMirrors real used car market value loss
Plant & Machinery (general)15–25%4–7 yearsVaries by asset type and intensity of use
Manufacturing Equipment15–20%5–7 yearsHeavy industrial assets often use lower rates
Office Furniture & Fittings10–15%7–10 yearsDesks, chairs, shelving — long-lived, lower rate
Tools & Equipment20–33%3–5 yearsSmaller tools depreciated quickly due to wear
Fixtures & Integral Features10%10 yearsHeating, lighting, electrics — mirrors HMRC 6% WDA broadly
Commercial BuildingsN/A — use SL20–50 yearsBuildings usually straight-line; use 3% SBA for tax
EV Charging Points25–33%3–4 yearsTechnology risk — faster depreciation appropriate
Long-Life Assets (25yr+)6–10%10–17 yearsLower rate; mirrors HMRC 6% special rate pool
HMRC Main Pool (proxy)14%~7 yearsMany businesses align accounting rates to HMRC WDA rates for simplicity

Related Calculators & Resources

Other UK depreciation tools and official guidance referenced on this page.

🔗 Related Calculators on This Site

🌐 Official UK Guidance & References

Frequently Asked Questions

Common questions about declining balance and reducing balance depreciation in the UK for 2026.

What is the reducing balance (declining balance) depreciation method?
The reducing balance method applies a fixed percentage to the asset's net book value (NBV) each year. The NBV reduces as depreciation is charged, which means the pound amount of the depreciation charge also falls each year — even though the percentage rate stays the same. For example, a £10,000 asset depreciated at 20% per year: Year 1 = £2,000 charge (NBV £8,000), Year 2 = £1,600 charge (NBV £6,400), Year 3 = £1,280 charge (NBV £5,120). The formula is: Depreciation = Net Book Value × Depreciation Rate. This is allowed under UK GAAP (FRS 102) and is widely used for motor vehicles, computers, plant and machinery.
What is the difference between reducing balance and straight-line depreciation?
Straight-line depreciation charges the same pound amount each year — calculated as (Cost − Residual Value) ÷ Useful Life. It fully writes the asset off to its residual value by the end of its useful life. Reducing balance charges a higher amount in early years that decreases each year. It never mathematically reaches zero (without a final write-off or switch). Straight-line is simpler and produces smoother profits. Reducing balance better reflects assets that lose value quickly in early life. Both are permitted under FRS 102 and neither is deductible for UK tax — HMRC uses its own capital allowance system instead. The choice should reflect the pattern in which the asset's economic benefits are consumed.
How do you calculate double declining balance depreciation?
Double declining balance (DDB) uses twice the straight-line rate applied to the remaining net book value each year. Step 1: Calculate the straight-line rate = 100% ÷ useful life in years. Step 2: Double it = DDB rate. Step 3: Apply DDB rate to opening NBV each year. For example, a 5-year asset has a straight-line rate of 20%, so the DDB rate is 40%. On a £50,000 asset: Year 1 = £50,000 × 40% = £20,000 depreciation (NBV £30,000). Year 2 = £30,000 × 40% = £12,000 (NBV £18,000). Year 3 = £18,000 × 40% = £7,200 (NBV £10,800). DDB produces the most front-loaded charges of all methods and is more common in US GAAP — it is used in UK GAAP where the asset loss pattern justifies it.
What declining balance rate should I use for a company vehicle in the UK?
For company cars and vans, UK businesses commonly use a reducing balance rate of 20–25% per year. A 20% rate means the vehicle retains 80% of its book value at the start of each year — producing a depreciation profile that broadly reflects real used car market behaviour. Some businesses align to the HMRC main pool WDA rate of 14% (from April 2026) for simplicity, as this avoids a large timing difference between accounting and tax calculations. The "right" rate under FRS 102 is whichever best matches the actual pattern of value consumption — for most UK commercial vehicles, 20–25% reducing balance is the most widely accepted practice. High-value luxury or sports cars may use a higher rate of 25–33% given their steeper initial market depreciation.
Can I claim reducing balance depreciation as a UK tax deduction?
No — reducing balance depreciation (like all accounting depreciation) is fully disallowed for UK tax purposes. On your CT600 Corporation Tax return or Self Assessment, the depreciation charge is added back to arrive at your adjusted profit. It is then replaced by the HMRC capital allowance claim — either the Annual Investment Allowance (AIA, 100% up to £1M), Full Expensing (100%, companies only), the new 40% First-Year Allowance (companies, from January 2026), or the Writing Down Allowance (14% main pool / 6% special rate from April 2026). This means that even if you use a 25% reducing balance in your accounts, the tax relief calculation is completely independent and based on HMRC's own rates and pools. See our HMRC Capital Allowances Calculator UK for the separate tax calculation.
Does reducing balance depreciation ever reach zero?
No — mathematically, reducing balance depreciation never reaches zero. Each year the charge is a percentage of a smaller number — the numbers get progressively smaller but never hit zero. In practice, UK businesses handle this in one of three ways. First, they set a residual value and stop depreciating when the NBV reaches that floor. Second, they switch to straight-line in later years when the straight-line charge (on the remaining balance over remaining life) exceeds the reducing balance charge — this is called the "switch" method and ensures full write-off by the end of useful life. Third, they simply write off the remaining balance when the asset is disposed of, creating a balancing charge or profit/loss on disposal in the accounts.
How do I record reducing balance depreciation in my UK accounts?
Reducing balance depreciation is recorded as a journal entry at the end of each accounting period. Debit the Depreciation Expense account (income statement / P&L) and credit the Accumulated Depreciation account (contra asset on the balance sheet). For example: on a van with a £9,600 annual reducing balance depreciation charge — Debit: Depreciation Expense £9,600. Credit: Accumulated Depreciation — Motor Vehicles £9,600. The van is shown on the balance sheet at its original cost (e.g. £48,000) less accumulated depreciation (e.g. £27,000) = Net Book Value £21,000. Most UK accounting software (Xero, QuickBooks, Sage) can automate this journal using the fixed asset register once you set the asset cost, date of purchase and depreciation method.
What happens to depreciation when I dispose of an asset?
When you sell or scrap an asset, you must remove it from the fixed asset register. Remove both the original cost and the accumulated depreciation from the balance sheet. The net book value at the disposal date is then compared to the disposal proceeds. If proceeds exceed NBV, there is a profit on disposal — credited to P&L. If proceeds are less than NBV, there is a loss on disposal — debited to P&L. For example, van with NBV of £24,576 sold for £18,000: loss on disposal = £6,576, charged to P&L. For tax purposes, disposal proceeds are deducted from the HMRC pool balance separately — this is an independent calculation that has no direct connection to the accounting profit or loss on disposal.
What are the four methods of depreciation used in the UK?
Under UK GAAP (FRS 102), there are four main methods recognised: (1) Straight-line method — equal annual charge over useful life, calculated as (Cost − Residual) ÷ Years. (2) Reducing balance method (declining balance) — fixed percentage applied to NBV each year, producing front-loaded charges. (3) Sum of the years' digits method (SYD) — a mathematical method that also front-loads depreciation but with a more gradual taper than reducing balance. (4) Units of production (activity) method — depreciation based on actual usage (machine hours, miles driven, units produced) rather than time. Of these, straight-line and reducing balance are by far the most commonly used in UK SME and large company accounts. The choice must reflect the actual pattern in which economic benefits are consumed.
Can I change my depreciation method under UK GAAP?
Yes, but only under specific circumstances. Under FRS 102, a change in depreciation method is treated as a change in accounting estimate — not a change in accounting policy. This means it is applied prospectively (going forward from the date of change) rather than restated retrospectively. The change is only permitted where the new method provides a more reliable and relevant measure of the asset's consumption pattern. For example, if evidence shows that a straight-line policy no longer matches the actual usage pattern of a fleet of vehicles, a switch to reducing balance is justified. The change, its reason and the financial effect must be disclosed in the notes to the accounts. You cannot change method simply to smooth profits or reduce a tax liability.
📉 Standard · Double Declining · Variable Rate — Updated 2026

Declining Balance Depreciation
Calculator UK

Free online reducing balance (declining balance) depreciation calculator for UK businesses and accountants. Generate a full year-by-year schedule showing net book value, annual depreciation charge and accumulated depreciation — with standard, double declining and variable annual rate modes. Covers UK GAAP FRS 102 and HMRC capital allowance context.

3
Calculation Modes
50yr
Max Projection Period
NBV
Net Book Value Per Year
FRS 102
UK GAAP Compliant Output
⚠️ Accounting vs Tax: The declining balance depreciation charge calculated on this page is your accounting depreciation for UK GAAP (FRS 102) purposes — it reduces your net book value and flows through your P&L. It is not the same as your HMRC capital allowance tax deduction. Accounting depreciation must be added back on your CT600 or Self Assessment and replaced with the HMRC Writing Down Allowance (WDA) or other capital allowance. See our HMRC Capital Allowances Calculator for the tax deduction.

📋 In This Page

  1. Declining Balance Depreciation Calculator — 3 Modes
  2. What Is Declining Balance (Reducing Balance) Depreciation?
  3. The Declining Balance Formula Explained
  4. Standard vs Double Declining vs Variable Rate — When to Use Each
  5. Worked Examples with Full UK Schedules
  6. Common UK Depreciation Rates by Asset Type
  7. Declining Balance vs Straight-Line — Side-by-Side
  8. UK GAAP FRS 102 and Declining Balance Depreciation
  9. Frequently Asked Questions

Declining Balance Depreciation Calculator UK

Three modes: standard reducing balance, double declining balance and fully custom variable annual rates. Each produces a complete year-by-year depreciation schedule.

📉 Standard Reducing Balance: A fixed annual percentage is applied to the asset's net book value at the start of each year — not the original cost. Produces a higher depreciation charge in earlier years that naturally reduces each year. This is the most common method used in UK business accounts and the default method for cars under HMRC capital allowances.
Enter the total purchase cost including delivery and installation.
Estimated value at end of ownership. Enter 0 if asset will be fully written down.
Apply to net book value each year. Common UK rates: 20–33% (plant), 25% (vehicles), 10–15% (fixtures).
For sole traders with private use — restrict depreciation to the business proportion.
📉📉 Double Declining Balance (DDB): The double declining balance method applies a rate that is twice the straight-line rate to the net book value each year. For example, an asset with a 5-year useful life has a straight-line rate of 20% — so DDB applies 40% per year. It is the most aggressive accelerated depreciation method and is more common in US GAAP, but can be used in UK management accounts where front-loaded charges are justified.
DDB rate = 2 ÷ Useful Life. E.g. 5-year life = 2/5 = 40% per year.
DDB stops depreciating once NBV reaches the residual value.
🎛️ Variable Annual Rates: Set a different depreciation rate for each year — reflecting real-world patterns where assets depreciate faster when new. Ideal for cars (higher Year 1 rate, lower thereafter), technology assets or any asset where depreciation is expected to change over time. Add up to 20 years with custom rates per year.

Set the depreciation rate (%) for each year: Leave a year blank to use the previous year's rate automatically.

What Is Declining Balance (Reducing Balance) Depreciation?

Declining balance depreciation — known in the UK as the reducing balance method — is an accounting method that calculates depreciation by applying a fixed percentage to the asset's net book value (NBV) at the start of each accounting period, rather than to the original purchase cost. Because the NBV falls each year, the depreciation charge also falls year on year — producing a front-loaded pattern that is higher in early years and lower as the asset ages.

This contrasts with the straight-line method, which charges the same fixed pound amount every year regardless of the asset's remaining value. The declining balance method is considered more economically realistic for many business assets — particularly vehicles, plant, machinery and technology — because it reflects the fact that assets tend to lose more value when they are newer and become more prone to maintenance costs as they age, creating a natural offset effect in the profit and loss account.

Under UK GAAP FRS 102, businesses can choose either straight-line or declining balance depreciation provided the chosen method best reflects the pattern in which the asset's future economic benefits are consumed. The method must be applied consistently year after year and disclosed in the accounting policies note of the financial statements. A change of method is only permitted where it produces a more reliable and relevant presentation and must be treated as a change in accounting estimate.

💡 UK naming note: The terms "declining balance", "reducing balance" and "diminishing value" are all used in UK accounting and tax contexts to describe the same method. "Declining balance" is the internationally recognised IFRS/IAS 16 term. "Reducing balance" is the more commonly used UK domestic term under FRS 102.

The Declining Balance Formula Explained

There are three versions of the formula depending on what you need to calculate:

🔢 Formula 1 — Annual Depreciation Charge
Depreciation This Year = Opening Net Book Value × Depreciation Rate

Apply this each year using the previous year's closing NBV as the new opening NBV.

🔢 Formula 2 — Net Book Value at End of Any Year
NBV at End of Year N = Original Cost × (1 − Rate) ^ N

The ^ symbol means "to the power of". This shortcut jumps directly to any future year without calculating each period individually.

🔢 Formula 3 — Double Declining Balance Rate
DDB Rate = 2 ÷ Useful Life in Years DDB Depreciation = DDB Rate × Opening Net Book Value

Example: A 5-year useful life gives DDB rate = 2 ÷ 5 = 40% per year applied to the remaining NBV.

🔢 Formula 4 — Find the Rate That Reduces to a Known Residual Value
Rate = 1 − (Residual Value ÷ Cost) ^ (1 ÷ Years)

Use this when you know the starting cost, the target residual value and the number of years — and want to work backwards to find the annual rate needed to reach that residual value.

Example: Formula 4 in Practice

Worked Example — Finding the Rate

A van costs £30,000. After 5 years you estimate it will be worth £6,000. What annual rate achieves this?

Formula: Rate = 1 − (6,000 ÷ 30,000)^(1/5)= 1 − (0.20)^0.20
(0.20)^0.20= 0.7248
Rate = 1 − 0.7248= 27.5% per year
✅ To depreciate a £30,000 van to a £6,000 residual over 5 years using reducing balance, apply a rate of approximately 27.5% per year.

Standard vs Double Declining vs Variable Rate — When to Use Each

All three are declining balance variants but suit different scenarios. Here is a practical guide:

📉 Standard Reducing Balance

NBV × Fixed Rate % each year
  • Most common UK accounting method under FRS 102
  • Consistent annual rate — easy to apply and explain
  • Reflects real-world asset value decline well
  • Used for vehicles, plant, machinery, computers
  • Rate chosen by management based on asset type
  • Asset never fully reaches £0 mathematically
  • Rate requires judgement — no single HMRC rate applies

📉📉 Double Declining Balance

NBV × (2 ÷ Useful Life) each year
  • Most aggressive accelerated depreciation method
  • Rate derived automatically from asset's useful life
  • Maximises front-loaded charges — useful for tax-aligned mgmt accounts
  • Common in US GAAP (IRS MACRS) contexts
  • Less commonly used in UK statutory accounts
  • May not match UK GAAP "pattern of consumption" requirement
  • Can overshoot residual value — needs a switch to straight-line

🎛️ Variable Annual Rates

Different % applied each year
  • Most realistic for cars (high Year 1, lower thereafter)
  • Matches HMRC WDA pool rate changes between periods
  • Can model real market value loss precisely
  • Useful for assets with known irregular depreciation patterns
  • More complex to set up and audit
  • Rate justification must be documented carefully

Worked Examples — Full UK Depreciation Schedules

Example 1 — Standard Reducing Balance: Company Van

Worked Example 1

Ford Transit Van — Purchased for £35,000, 25% reducing balance, 5-year projection

YearOpening NBVDepreciation (25%)Acc. DepreciationClosing NBVTax Saving (25% CT)
2026£35,000£8,750£8,750£26,250£2,188
2027£26,250£6,563£15,313£19,688£1,641
2028£19,688£4,922£20,234£14,766£1,230
2029£14,766£3,691£23,926£11,074£923
2030£11,074£2,769£26,695£8,306£692
Total—£26,695—£8,306£6,674
✅ After 5 years, the van has a net book value of £8,306 (23.7% of original cost). Total depreciation charged: £26,695. Estimated Corporation Tax saving over 5 years (note: actual tax relief via HMRC capital allowances, not this accounting figure): £6,674.

Example 2 — Double Declining Balance: Manufacturing Equipment

Worked Example 2

CNC Milling Machine — £120,000 cost, 10-year useful life, DDB rate = 20% (2 ÷ 10), residual £5,000

YearOpening NBVDDB Charge (20%)Closing NBV
2026£120,000£24,000£96,000
2027£96,000£19,200£76,800
2028£76,800£15,360£61,440
2029£61,440£12,288£49,152
2030£49,152£9,830£39,322
2031£39,322£7,864£31,457
2032£31,457£6,291£25,166
2033£25,166£5,033£20,133
2034£20,133£4,027£16,106
2035£16,106£3,221£12,885
Total (10 yrs)—£107,114£12,885
✅ Over 10 years at DDB 20%, the machine has a closing NBV of £12,885 — above the £5,000 residual. In practice, depreciation would stop when NBV reaches the £5,000 residual value. Total depreciation: £107,114 (89.3% of cost).

Example 3 — Variable Rates: Company Car (Realistic UK Market Pattern)

Worked Example 3 — Variable Rates

BMW 5 Series — £55,000, Year 1: 30%, Years 2–3: 18%, Years 4–5: 12%

YearRateOpening NBVDepreciationClosing NBV% of Cost Retained
202630%£55,000£16,500£38,50070.0%
202718%£38,500£6,930£31,57057.4%
202818%£31,570£5,683£25,88847.1%
202912%£25,888£3,107£22,78141.4%
203012%£22,781£2,734£20,04736.4%
Total——£34,953£20,04736.4%
✅ After 5 years this BMW has an estimated accounting NBV of £20,047 (36.4% retained). Total depreciation charged through P&L: £34,953. The variable rate pattern closely mirrors actual UK used car market residual values for this segment.

Common UK Declining Balance Depreciation Rates by Asset Type (2026)

UK GAAP (FRS 102) does not prescribe specific depreciation rates — management must select rates that best reflect the pattern in which the asset's economic benefits are consumed. The rates below are the most commonly used in UK accounting practice. Always document the basis for your chosen rate in your accounting policies.

Asset TypeTypical UK Rate (RB)Useful Life EquivalentNotes
Cars and Vans (general)20–33%3–5 years25% is the most common rate for company vehicles
Plant & Machinery (general)15–25%4–7 yearsHigher rate for equipment with rapid obsolescence
Computers & Laptops25–33%3–4 yearsTechnology assets depreciate quickly — use higher rate
Office Furniture & Fittings10–20%5–10 years10–15% common for quality commercial furniture
Office Equipment (printers, phones)20–33%3–5 yearsAlign with manufacturer's expected product lifespan
Agricultural Machinery15–20%5–7 yearsVaries widely by equipment type and usage intensity
Manufacturing Equipment (heavy)10–20%5–10 yearsCNC machines, presses — longer life, lower rate
Commercial Vehicles (HGVs)20–25%4–5 yearsHigh-mileage trucks may justify the higher end
Fixtures & Fittings (shop/office fit-out)10–15%7–10 years15% for leasehold premises with shorter expected life
Electronic Testing Equipment20–25%4–5 yearsTechnology risk supports higher rate
Leasehold ImprovementsStraight-line over lease termLease termUsually straight-line is more appropriate here
EV Charging Equipment15–25%4–7 yearsTechnology evolution supports higher depreciation rate
HMRC Main Pool WDA (tax, not accounting)14% from Apr 2026—Tax deduction only — add back accounting dep. on CT600
💡 Tip: Your accounting depreciation rate and the HMRC WDA rate are completely separate. A van depreciated at 25% in your accounts and 14% in the HMRC main pool will create a timing difference (deferred tax) each year. The two figures only converge if the asset is disposed of for its exact net book value.

Declining Balance vs Straight-Line — Side by Side

Choosing between the two methods depends on the asset type and the economic reality of how it loses value. Here is a direct comparison using the same £40,000 asset over 5 years:

YearSL Annual ChargeSL NBVRB Annual Charge (25%)RB NBVDifference (RB − SL)
Year 1£8,000£32,000£10,000£30,000+£2,000 (RB higher)
Year 2£8,000£24,000£7,500£22,500−£500 (SL higher)
Year 3£8,000£16,000£5,625£16,875−£2,375 (SL higher)
Year 4£8,000£8,000£4,219£12,656−£3,781 (SL higher)
Year 5£8,000£0£3,164£9,492−£4,836 (SL higher)
Total (5 yrs)£40,000£0£30,508£9,492—

Straight-line: (£40,000 − £0) ÷ 5 = £8,000/yr. Reducing balance: 25% on reducing NBV. Residual £0 assumed for SL.

Key insight: Straight-line charges more in years 3–5, while reducing balance charges more in year 1. Over the full asset life, straight-line generates greater total relief where residual value is zero — reducing balance leaves a residual tail (£9,492 in this example) that must be cleared via a balancing charge/allowance on disposal.

UK GAAP FRS 102 and Declining Balance Depreciation

Under FRS 102 Section 17 (Property, Plant and Equipment), UK entities must depreciate all tangible fixed assets (other than those with an indefinite useful life) over their useful economic life. The standard requires that the depreciation method chosen should reflect the pattern in which the asset's future economic benefits are expected to be consumed by the entity.

What FRS 102 Requires

  • The depreciation method, useful life and residual value must be reviewed at each balance sheet date and changed if expectations differ materially from previous estimates
  • A change in method is treated as a change in accounting estimate (prospective, not a restatement), not a change in accounting policy
  • The depreciation method and rate used must be disclosed in the accounting policies section of the notes to the financial statements
  • For micro-entities (FRS 105), depreciation must still be calculated on all fixed assets but reduced disclosure is permitted
  • Where an asset has components with significantly different useful lives, each component should be depreciated separately (component accounting)

Choosing the Right Method Under FRS 102

For most plant, machinery, vehicles and technology assets, the reducing balance method is the preferred UK approach because it produces higher charges when the asset is most productive and its value decline is steepest. Straight-line may be more appropriate for assets that provide broadly consistent economic benefits year after year — such as leasehold improvements or commercial buildings where physical deterioration is gradual and predictable.

💡 FRS 102 Practical Tip: For small company accounts, consistency is key. Choose your rate, document it in your accounting policies, apply it every year to the same asset class, and do not change it without a genuine change in the expected pattern of benefit consumption. Auditors and HMRC compliance checks specifically look for unexplained rate changes between periods.

Useful Resources

Related calculators and official guidance referenced throughout this page.

🔗 Related Calculators on This Site

🌐 Official & External UK Sources

Frequently Asked Questions

Common questions about declining balance (reducing balance) depreciation for UK businesses.

What is the declining balance (reducing balance) depreciation formula in the UK?
There are three key formulas. For the annual charge: Depreciation = Opening Net Book Value × Annual Rate. For the closing net book value at any year: NBV = Original Cost × (1 − Rate)^N, where N is the number of years. For double declining balance: DDB Rate = 2 ÷ Useful Life in Years, then DDB Depreciation = DDB Rate × Opening NBV. For example, a £20,000 asset depreciated at 20% reducing balance: Year 1 depreciation = £20,000 × 20% = £4,000 (NBV: £16,000). Year 2 = £16,000 × 20% = £3,200 (NBV: £12,800). The charge decreases every year because it is always applied to the remaining value, not the original cost.
What is the difference between declining balance and reducing balance depreciation?
There is no meaningful difference — "declining balance" and "reducing balance" describe the same depreciation method. "Reducing balance" is the preferred UK domestic accounting term used under FRS 102 and by UK accountants, HMRC and Companies House guidance. "Declining balance" is the internationally recognised term used in IAS 16 (IFRS) and is commonly used in US, Australian and international accounting contexts. The calculation is identical in both cases: a fixed percentage applied to the asset's net book value at the start of each period. "Diminishing value" is another synonymous term occasionally used in UK tax and accountancy literature.
What reducing balance depreciation rate should I use in the UK?
UK GAAP (FRS 102) does not prescribe specific rates — you must choose a rate that best reflects the pattern in which the asset's future economic benefits are consumed. Common UK practice rates are: cars and vans 20–33% (25% most common), computers and laptops 25–33%, general plant and machinery 15–25%, office furniture and fittings 10–20%, heavy manufacturing equipment 10–20%, commercial vehicles 20–25%, office equipment 20–33%. You should document your chosen rate in the accounting policies note of your financial statements and apply it consistently to the same class of assets across all accounting periods. If you are unsure, speak to your accountant — the rate should reflect the specific asset's expected useful economic life and the pace at which you will consume its economic benefits.
Can I use declining balance depreciation for my HMRC tax return?
No — your accounting depreciation (whether straight-line or reducing balance) is not the same as your HMRC capital allowance. For tax purposes, accounting depreciation is added back to your profits on the CT600 (Corporation Tax) or Self Assessment and replaced with the appropriate HMRC capital allowance. The main HMRC allowances for 2026 are: AIA 100% (up to £1M for all businesses), Full Expensing 100% (companies only, no cap, new assets), 40% FYA (companies only, from January 2026), 14% WDA on the main pool (reduced from 18% from April 2026) and 6% WDA on the special rate pool. Cars specifically cannot use AIA or Full Expensing — they use HMRC's CO₂-based rates of 100% FYA (EVs), 14% WDA (1–50g/km) or 6% WDA (51g/km+).
What is double declining balance depreciation and is it used in the UK?
Double declining balance (DDB) depreciation applies a rate that is exactly twice the equivalent straight-line rate to the net book value each year. For a 5-year asset, the straight-line rate is 20%, so DDB applies 40% per year to the declining balance. It is the most aggressive form of accelerated depreciation. DDB is the standard accelerated method under US GAAP (the IRS MACRS system) and is widely used in American accounting. In the UK, it is less commonly used for statutory accounts under FRS 102 — UK accountants typically use standard reducing balance at a rate chosen to reflect the asset's economic life, rather than the mechanically derived DDB rate. However, DDB can be used in UK management accounts and internal reporting where front-loaded charges are considered a better reflection of the asset's pattern of benefit consumption.
Why does a declining balance asset never reach zero?
Mathematically, applying a fixed percentage to a declining balance means the charge gets smaller every year but the balance never actually reaches zero — it just approaches it asymptotically. For example, a £10,000 asset at 20% reducing balance will have a value of £1,073 after 10 years, £115 after 20 years and so on — it never hits zero by the formula alone. In practice, this is handled in two ways. First, most businesses set a residual value (the estimated scrap or resale value) and stop depreciating once the NBV reaches that figure. Second, when the asset is eventually disposed of, sold or scrapped, a balancing allowance (for tax) or a gain/loss on disposal (for accounts) deals with any remaining balance. There is no requirement to continue carrying a nominal balance indefinitely — practical judgement is applied.
Can I switch from straight-line to reducing balance depreciation in the UK?
Yes — under FRS 102, you can change your depreciation method, but only where the new method gives a more reliable and relevant presentation of how the asset's economic benefits are consumed. A change of depreciation method is treated as a change in accounting estimate, not a change in accounting policy. This means it is applied prospectively from the date of change — you do not restate prior years. The remaining net book value at the date of change is depreciated over the remaining useful life using the new method. The change and its reason must be disclosed in the notes to the financial statements in the year of change. Changing methods simply to smooth profits or reduce tax would not be an acceptable reason under FRS 102 — the change must be genuinely justified by a change in the expected pattern of benefit consumption.
How do I calculate the declining balance rate needed to reach a specific residual value?
Use the reverse formula: Rate = 1 − (Residual Value ÷ Original Cost)^(1 ÷ Years). For example, you buy an asset for £50,000 and want it to have a net book value of £8,000 after 6 years. Rate = 1 − (8,000 ÷ 50,000)^(1/6) = 1 − (0.16)^0.1667 = 1 − 0.7182 = 0.2818 = approximately 28.2% per year. Applying 28.2% reducing balance to £50,000 for 6 years produces a closing NBV of approximately £8,000. You can use this formula whenever you know the start value, target end value and time period and need to work backwards to find the annual rate. This is particularly useful for car depreciation planning where you have a reliable residual value estimate from a trade guide.
What happens to the reducing balance when I sell or dispose of an asset?
When you dispose of an asset, you compare the disposal proceeds (sale price, trade-in value or nil if scrapped) against the asset's net book value at the date of disposal. If proceeds exceed NBV, the difference is a profit on disposal — credited to the P&L. If NBV exceeds proceeds, the difference is a loss on disposal — charged to the P&L. For example, a van with NBV of £12,000 sold for £9,500 generates a loss on disposal of £2,500. This is entirely separate from the HMRC capital allowances position on the same asset — for tax, the disposal proceeds are deducted from the relevant pool balance, potentially triggering a balancing allowance or balancing charge. Always reconcile both the accounting and tax treatment on disposal to avoid errors on your CT600.
Is reducing balance better than straight-line for UK business accounts?
Neither is universally "better" — FRS 102 requires you to choose the method that best reflects how the asset's economic benefits are consumed. For most vehicles, plant and technology assets, reducing balance is more appropriate because these assets genuinely lose more value when new. It also produces a natural financial offset — as depreciation charges fall with age, maintenance costs tend to rise, producing a broadly smoothed total asset cost through the P&L over the asset's life. For assets with steady economic output over their lives — leasehold improvements, moulds, or certain fixtures — straight-line is typically more appropriate. For practical purposes, both methods are equally acceptable under FRS 102, equally disallowed for Corporation Tax (add back and replace with HMRC capital allowances), and both equally valid for financial statement purposes provided they are applied consistently and disclosed in the accounting policies note.