On 1 April 2026, the main rate of Writing Down Allowance for plant and machinery fell from 18% to 14%. This is not a minor administrative adjustment — it is the most significant reduction in the WDA main rate in over a decade, and it affects every healthcare practice in England and Wales that holds a capital allowances pool. The change was confirmed in the Autumn Budget 2024, legislated in the Finance Act 2025, and is now live.

For GP surgeries, dental practices, pharmacies, private clinics, and care homes that have been claiming Writing Down Allowances on equipment, fixtures, and fittings, the reduction means the tax relief available each year on their existing pool balance has fallen materially. A pool balance of £200,000 that generated £36,000 of tax relief in 2025/26 at 18% now generates only £28,000 at 14% — a reduction of £8,000 in deductible expenditure from a single change in rate.

This guide explains exactly what has changed, how the hybrid rate calculation works for accounting periods that span 1 April 2026, what healthcare practices with existing pool balances need to recalculate, and where the new 40% First Year Allowance introduced in January 2026 creates a planning opportunity to offset the impact of the WDA reduction.

What Changed and Why

The Writing Down Allowance is the annual tax deduction available on the reducing balance of a capital allowances pool — the accumulated value of assets that have not been fully relieved through the Annual Investment Allowance, Full Expensing, or other first-year allowances. Every year, a percentage of the pool balance is deducted as a business expense, reducing taxable profit.

Until 31 March 2026, the main pool WDA rate was 18% per year. From 1 April 2026, it is 14%. The special rate pool — covering integral features of buildings, long-life assets, and thermal insulation — remains unchanged at 6% per year.

The government’s rationale for the WDA reduction is that it is partially offset by the introduction of the new 40% First Year Allowance for main rate assets (introduced from 1 January 2026 for businesses that cannot claim Full Expensing — primarily unincorporated businesses and leasing companies). The argument is that front-loading relief through the 40% FYA compensates for the slower write-down rate on the residual pool. In practice, this trade-off only works in favour of healthcare practices that are actively investing in new equipment. Practices with large existing pools and modest new investment receive no benefit from the 40% FYA and simply see their annual WDA reduce.

Key Point: The WDA rate cut affects your existing pool balance immediately — there is no transitional protection for assets already in the pool. Every £1 of pool balance that was being written down at 18% is now written down at 14%. If your practice has a significant pool, the impact on your annual tax deduction is material from the first accounting period that falls after 1 April 2026.

The Hybrid Rate: How It Works for Periods Spanning 1 April 2026

The WDA rate change does not simply apply from the start of your next accounting period — it applies proportionately to any accounting period that straddles 1 April 2026. This hybrid rate calculation is the most immediately practical issue for healthcare practices whose financial year does not run to 31 March.

How the hybrid rate is calculated:

For an accounting period that spans 1 April 2026, HMRC applies a blended WDA rate based on the number of days before and after 1 April 2026 within that period.

The formula is:

Hybrid rate = (Days before 1 April 2026 ÷ Total days in period × 18%) + (Days after 1 April 2026 ÷ Total days in period × 14%)

Worked Example — Practice with a 31 December year-end:

A GP surgery with a 31 December year-end has an accounting period running from 1 January 2026 to 31 December 2026 — a period of 365 days.

Days before 1 April 2026: 90 days (January, February, March) Days from 1 April 2026 onwards: 275 days (April through December)

Hybrid rate = (90 ÷ 365 × 18%) + (275 ÷ 365 × 14%) Hybrid rate = (0.2466 × 18%) + (0.7534 × 14%) Hybrid rate = 4.44% + 10.55% Hybrid rate = 14.99% (effectively 15% for this period)

Worked Example — Practice with a 30 April year-end:

A dental practice with a 30 April year-end has an accounting period from 1 May 2025 to 30 April 2026 — a period of 365 days.

Days before 1 April 2026: 335 days (May 2025 through March 2026) Days from 1 April 2026 onwards: 30 days (April 2026)

Hybrid rate = (335 ÷ 365 × 18%) + (30 ÷ 365 × 14%) Hybrid rate = (0.9178 × 18%) + (0.0822 × 14%) Hybrid rate = 16.52% + 1.15% Hybrid rate = 17.67% (effectively 17.7% for this period)

The practical takeaway:

The hybrid rate means that practices whose year-end falls shortly after 1 April 2026 — such as 30 April or 31 May — experience very little change in their WDA for the current year. The full impact of the 14% rate is felt from the first complete accounting period that begins on or after 1 April 2026. For most practices with March year-ends, 2026/27 is effectively the first full year at 14%. For practices with later year-ends, the transition is more gradual.

Your healthcare accountant should be calculating the hybrid rate applicable to your accounting period now — not at year-end — so that quarterly management accounts and tax reserve planning reflect the correct WDA deduction for 2026/27.

The Financial Impact by Pool Balance: Worked Examples Across Practice Types

To make the impact concrete, here are worked examples across the main healthcare practice types, showing the difference between the old 18% rate and the new 14% rate on typical pool balances.

Example 1 — GP Surgery

A GP surgery has a main pool balance of £85,000 at the start of its accounting period beginning 1 April 2026 (no new qualifying expenditure in this example).

At 18%: WDA = £85,000 × 18% = £15,300 — closing pool balance £69,700 At 14%: WDA = £85,000 × 14% = £11,900 — closing pool balance £73,100

Annual difference: £3,400 less tax relief per year.

At a 20% income tax rate (partnership): £680 more tax payable than under the old rate. At a 45% additional rate (high-earning GP partner): £1,530 more tax payable.

Example 2 — Dental Practice (Limited Company)

A dental practice operating as a limited company has a main pool balance of £220,000 at the start of its accounting period beginning 1 April 2026.

At 18%: WDA = £220,000 × 18% = £39,600 — closing pool balance £180,400 At 14%: WDA = £220,000 × 14% = £30,800 — closing pool balance £189,200

Annual difference: £8,800 less tax relief per year.

At 25% corporation tax rate: £2,200 more corporation tax payable than under the old rate — simply from the rate change, with no other change in the practice’s affairs.

Example 3 — Community Pharmacy

A community pharmacy has a main pool balance of £150,000, comprising dispensing automation, refrigeration units, point-of-sale systems, and shop fittings.

At 18%: WDA = £150,000 × 18% = £27,000 — closing pool balance £123,000 At 14%: WDA = £150,000 × 14% = £21,000 — closing pool balance £129,000

Annual difference: £6,000 less tax relief per year.

At 45% additional rate (pharmacy owner drawing significant income): £2,700 more income tax payable per year on identical profits.

Example 4 — Care Home

A care home has a main pool balance of £380,000, reflecting substantial investment in resident room furniture, communal area fittings, kitchen equipment, laundry machinery, and care technology.

At 18%: WDA = £380,000 × 18% = £68,400 — closing pool balance £311,600 At 14%: WDA = £380,000 × 14% = £53,200 — closing pool balance £326,800

Annual difference: £15,200 less tax relief per year.

At 25% corporation tax rate: £3,800 more corporation tax payable per year.

Important: These examples use static pool balances with no new investment. In practice, new qualifying expenditure added to the pool via AIA or WDA also attracts the 14% rate on any balance remaining after first-year relief. The interaction between new investment, AIA claims, and the reduced WDA rate needs to be modelled for each practice individually. Our business tax team can run this analysis for your specific pool position.

What Healthcare Practices Need to Recalculate Right Now

The WDA rate change requires several specific recalculations that should be completed as a matter of priority for the 2026/27 tax year.

1. Recalculate your tax reserve or payment on account

If your practice makes payments on account — as most sole traders and partnerships do — the payment on account for January 2027 (based on 2025/26 liability) may understate your true 2026/27 liability if the WDA reduction significantly increases taxable profit. This is not an immediate cash crisis but it is a cash flow planning issue worth quantifying now. Practices that have relied on a high WDA deduction to keep taxable profit low may find their 2026/27 liability meaningfully higher than their current payment on account.

2. Recalculate management account profitability projections

If your 2026/27 management accounts were prepared using a budgeted WDA at 18%, they need to be updated. Using the wrong rate understates projected taxable profit and gives partners or directors a misleadingly optimistic picture of distributable profit. Sound bookkeeping for healthcare practices produce management accounts that reflect the correct tax position — including the updated WDA rate — on a monthly basis.

3. Recalculate partner drawings budgets for GP practices

For GP partnerships, the level of monthly drawings taken by partners should be based on a realistic projection of the year-end profit after all allowable deductions including WDA. If the WDA deduction has fallen by £5,000–£15,000 due to the rate change, the safe level of monthly drawings is correspondingly lower. Overly generous drawings based on the old WDA assumption can leave a partnership short at year-end when the tax liability is settled. Our GP practice accounting team reviews drawing levels for all partnership clients at the start of each tax year — if you have not had this conversation yet for 2026/27, now is the time.

4. Recalculate the hybrid rate for the current accounting period

As demonstrated above, the hybrid rate applicable to your current accounting period depends on your year-end. Establish the correct hybrid rate for your period now and apply it to your opening pool balance. Do not apply either 18% or 14% in full to a period that straddles 1 April 2026 — both would be incorrect and could result in either an underpayment or overpayment of tax.

5. Review your special rate pool separately

The special rate pool rate remains at 6% per year — unchanged. If your practice has a meaningful special rate pool (integral features of your building, long-life assets), ensure this is being tracked separately from the main pool and written down at 6%. Practices that commingle main pool and special rate pool assets lose the ability to apply the correct rate to each and may be under-claiming or over-claiming relief.

The New 40% First Year Allowance: The Offsetting Opportunity

The government introduced the 40% First Year Allowance for main rate assets from 1 January 2026 specifically as a partial offset to the WDA rate reduction. Understanding how this new allowance works — and which healthcare practices can use it — is essential to planning around the WDA cut.

What the 40% FYA covers:

The 40% FYA applies to new expenditure on main rate plant and machinery that would otherwise go into the main pool at 14% WDA. Rather than adding the expenditure to the pool and claiming 14% in year one, a practice can instead claim 40% of the cost as a first-year allowance — dramatically accelerating the relief.

Who can claim the 40% FYA:

The 40% FYA is specifically designed for businesses that cannot claim Full Expensing — primarily unincorporated businesses (sole traders and partnerships) and businesses involved in leasing. GP partnerships and sole trader locums that have historically been unable to benefit from Full Expensing (which is restricted to companies) can now claim this enhanced first-year relief.

Limited companies can still claim Full Expensing (100% in year one) on new plant and machinery and are therefore less directly affected by the 40% FYA — though they benefit from it on assets that fall outside the Full Expensing scope.

Worked Example — 40% FYA vs WDA for a GP Partnership:

A GP partnership buys a new ECG machine for £15,000 in May 2026. The practice has already used its AIA for the year on other equipment.

Without the 40% FYA (WDA only): Year 1 WDA: £15,000 × 14% = £2,100 Year 2 WDA: £12,900 × 14% = £1,806 Year 3 WDA: £11,094 × 14% = £1,553 Total relief in 3 years: £5,459

With the 40% FYA: Year 1 FYA: £15,000 × 40% = £6,000 Remaining pool: £9,000 Year 2 WDA: £9,000 × 14% = £1,260 Year 3 WDA: £7,740 × 14% = £1,084 Total relief in 3 years: £8,344

The 40% FYA delivers £2,885 more relief in the first three years — a meaningful acceleration even after the WDA rate cut.

The interaction with the Annual Investment Allowance:

The 40% FYA is most relevant where a practice has already exhausted its AIA for the year. For most independent healthcare practices, the £1,000,000 AIA limit means virtually all equipment purchases can be fully relieved in year one via the AIA anyway — making the 40% FYA less immediately relevant in practice. However, for larger group practices, associated entities where the AIA is shared, or practices investing heavily in a single year across multiple entities, the 40% FYA provides a valuable additional layer of first-year relief.

Discuss with your specialist healthcare accountant whether the 40% FYA applies to any expenditure your practice is planning for 2026/27 and whether it should be claimed in preference to adding the expenditure to the main pool at 14%.

Special Rate Pool: Unchanged at 6% But Worth Reviewing

While the main pool WDA has fallen to 14%, the special rate pool remains at 6% per year. The special rate pool covers:

• Integral features of buildings: electrical systems, cold water systems, heating and ventilation (HVAC), lifts, solar panels
• Long-life assets with an expected working life of 25 years or more
• Thermal insulation added to existing buildings

For healthcare practices that have carried out significant building works — fitting out a new surgery, converting premises into a clinic, or refurbishing a care home — a portion of those costs will have been allocated to the special rate pool. At 6% per year, the write-down is very slow — a £100,000 special rate pool balance takes approximately 37 years to fully relieve on a reducing balance basis.

The 50% First Year Allowance for special rate assets:

Companies can claim a 50% First Year Allowance on new special rate assets in the year of purchase rather than adding them to the special rate pool at 6%. This remains unchanged and is highly valuable for incorporated dental practices, private hospitals, and care home companies investing in major building integral features. The 50% FYA on special rate assets effectively halves the time to full relief on these slow-depreciating assets.

The Structures and Buildings Allowance interaction:

Practices should ensure that expenditure on building works has been correctly split between plant and machinery (main pool or special rate pool, as appropriate) and structural expenditure (Structures and Buildings Allowance at 3% per year). Misclassifying structural expenditure as special rate pool — or vice versa — results in either an incorrect WDA claim or a missed SBA claim. This split should be reviewed by a capital allowances specialist at the time of any significant building expenditure, not retrospectively at year-end.

Planning Opportunities Created by the Rate Change

The WDA rate reduction is not purely a tax cost — it creates several planning opportunities for healthcare practices that approach it proactively.

Accelerate new equipment purchases into 2026/27 using the 40% FYA

For unincorporated practices that have exhausted or are approaching their AIA limit, any new main rate equipment purchased in 2026/27 can benefit from the 40% FYA rather than the 14% WDA. Timing equipment purchases to fall within the current tax year rather than the next maximises the first-year benefit.

Consider whether incorporation changes the calculus

The WDA rate cut affects both incorporated and unincorporated practices equally. However, Full Expensing — which remains available only to companies — provides 100% first-year relief with no upper limit on new plant and machinery. For a GP partnership or sole trader pharmacy owner who is considering incorporating, the Full Expensing benefit becomes relatively more attractive now that the unincorporated WDA rate has fallen to 14%. This is not a decision to make on the basis of capital allowances alone, but it is a factor worth including in any incorporation analysis. Our personal tax and business tax teams regularly advise healthcare professionals on the full tax implications of incorporation.

Review the pool balance for disposal planning

If your practice is planning to dispose of assets — old equipment, fixtures from a premises refurbishment, or vehicles — the timing of those disposals relative to your year-end affects the WDA calculation. When an asset is disposed of, the proceeds are deducted from the pool balance before WDA is applied. Disposing of assets early in the accounting period therefore reduces the pool balance on which WDA is calculated — which at 14% is less valuable than it was at 18%. This is a relatively minor consideration but worth factoring into disposal timing decisions.

Consider pension contributions as a complementary tax planning tool

With the WDA rate cut reducing the automatic tax relief flowing from the capital allowances pool, some healthcare professionals may find that increasing pension contributions is a more efficient way to manage taxable profit in 2026/27. Pension contributions remain fully deductible for income tax and corporation tax purposes and — unlike WDA — reduce the tax base immediately and completely rather than on a reducing balance over many years. Our personal tax team for healthcare professionals can model the combined effect of WDA, pension contributions, and other deductions to identify the optimal planning position for your 2026/27 year.

How This Interacts With the Capital Allowances Changes We Have Already Covered

If you have read our earlier guide on capital allowances for medical equipment, you will know that the full capital allowances landscape for healthcare practices in 2026 is complex — with the AIA at £1,000,000, Full Expensing for companies, the new 40% FYA for unincorporated businesses, the SBA at 3%, and now the WDA main rate at 14% rather than 18%.

The WDA reduction adds an additional layer to that landscape. The key updated principles for 2026/27 are:

For unincorporated practices (GP partnerships, sole trader pharmacists, locum doctors): use the AIA first to get 100% relief in year one on all qualifying expenditure up to £1,000,000. For any expenditure above the AIA limit — or in years where the AIA has been exhausted — use the new 40% FYA on main rate assets rather than letting expenditure fall into the pool at 14% WDA. The special rate pool at 6% should be minimised through the 50% FYA where possible, though this is only available to companies.

For incorporated practices (dental companies, private clinic limited companies, care home groups): use Full Expensing on all new main rate plant and machinery (100% in year one, no upper limit). Use the 50% FYA on new special rate assets. The WDA at 14% only applies to residual pool balances from prior years and to assets that do not qualify for Full Expensing — such as second-hand equipment, cars, and assets used partly for non-business purposes.

Our guide on capital allowances changes April 2026 covers the broader package of changes that came into force this month. Read both guides together to get the complete picture of where your practice stands on capital allowances for 2026/27.