The 2025/26 tax year ends on 5 April 2026. Once it is gone, most tax-saving opportunities vanish with it. Here is everything high earners should check, claim, and action before the deadline.
Most UK tax allowances and reliefs are "use it or lose it" — they cannot be carried into the next tax year. If you earn over £50,000, the amount you can save by acting before 5 April is often in the thousands.
This checklist covers every major action item for 2025/26, prioritised by impact. Some take 5 minutes. Others need a few days to arrange. Start now — some actions (like salary sacrifice changes) require employer processing time.
This is the single highest-impact action for most high earners. Pension contributions reduce your adjusted net income, which can:
Escape the 60% trap: If you earn between £100,000 and £125,140, pension contributions restore your personal allowance. Every £2 contributed effectively saves £1.20 in tax (60% relief). Use our 60% trap analysis tool to see your exact exposure.
Eliminate the child benefit charge: If you earn between £60,000 and £80,000 and have children, pension contributions can bring you below the £60,000 threshold — keeping your full child benefit. See our HICBC guide.
Get higher-rate relief: Even without the trap, 40% and 45% taxpayers get £400–£450 back for every £1,000 contributed.
The annual allowance is £60,000 for 2025/26. If you have not used your full allowance in previous years (2022/23, 2023/24, 2024/25), you can carry forward the unused amount — potentially contributing well over £100,000 this year. Check your pension provider statements to calculate your unused allowance.
Deadline alert: Personal pension contributions must reach your provider by 5 April 2026. Do not leave this to the last week — bank transfers can take 3-5 working days to clear.
If your employer offers salary sacrifice for pension, this saves both income tax and National Insurance — unlike personal contributions which only save income tax. For a higher-rate taxpayer, the NI saving alone is worth 2% on income above £50,270.
Many employers also pass on their own NI saving (15%) into your pension pot, adding an extra £1,500 for every £10,000 sacrificed.
If you have not set up salary sacrifice yet, ask your HR department now. Some employers have processing deadlines, so you may need to act quickly to get a sacrifice in place before 5 April. See our salary sacrifice guide for worked examples.
The ISA allowance for 2025/26 is £20,000 — and it cannot be carried forward. Investments inside an ISA grow completely tax-free: no income tax on interest, no dividend tax, no capital gains tax.
With the dividend allowance slashed to £500 and the CGT exemption at just £3,000, the value of ISA sheltering has never been higher. If you have investments sitting in a general investment account (GIA), consider a "Bed and ISA" — sell holdings in your GIA and immediately repurchase them inside your ISA. This crystallises a disposal for CGT purposes, so stay within your £3,000 annual exemption.
If you have already used your £3,000 CGT allowance or have large gains, spread the Bed and ISA across tax years — sell up to £3,000 of gains before 5 April and another £3,000 after.
The ISA allowance resets on 6 April. Any unused portion from 2025/26 is gone forever. Even if you can only fund part of it, every pound sheltered saves future tax.
The annual CGT exemption for 2025/26 is £3,000 per person (£6,000 for couples who both have gains). If you have investments with unrealised gains, consider selling enough to use the exemption before 5 April.
Common strategies:
Bed and ISA: Sell shares in a GIA, repurchase inside your ISA. The gain up to £3,000 is tax-free, and future growth is permanently sheltered.
Bed and spouse: Transfer assets to your spouse (tax-free between spouses), who then sells using their own £3,000 allowance. This doubles the exemption for couples.
Rebalancing: If you need to rebalance your portfolio, do it before 5 April to use the exemption on any gains that arise.
If one partner earns less than £12,570 and the other is a basic-rate taxpayer (earning £12,571–£50,270), you can transfer £1,260 of the personal allowance — saving £252 per year.
Crucially, you can backdate by 4 years. If you have been eligible since 2021/22 and have not claimed, you could receive a lump sum of up to £1,008 plus the current year saving. This takes 5 minutes on GOV.UK.
See our marriage allowance guide for full eligibility rules and how to claim. Note: this does not apply if the higher earner pays 40% or 45% tax — it is specifically for basic-rate taxpayers.
An incorrect tax code can mean you have overpaid tax all year. Common errors include:
Stale emergency tax codes — if you changed jobs during the year, you may still be on a cumulative emergency code.
Missing allowances — marriage allowance, professional subscriptions, or work-from-home relief may not be reflected in your code.
Incorrect benefit-in-kind values — company car, private medical insurance, or other benefits may have changed but HMRC still uses old figures.
Check your tax code on your payslip or through your HMRC Personal Tax Account online. If it looks wrong, call HMRC on 0300 200 3300 or update it online. An overpayment this year will be refunded, but it is better to get it right now than wait for reconciliation in the summer. Use our tax code decoder to understand what your code means.
If you are a higher-rate (40%) or additional-rate (45%) taxpayer, every £100 you donate to charity through Gift Aid costs you only £60 (or £55 at the additional rate) after claiming all reliefs.
Gift Aid donations also extend your basic-rate band — reducing your adjusted net income. This interacts with the 60% trap: a £1,000 gross Gift Aid donation in the taper band effectively saves you £600 in tax.
Make sure all charitable donations before 5 April are Gift Aid eligible, and keep records. If you file self-assessment, include these on your return to claim the higher-rate relief. If you do not file self-assessment, call HMRC to adjust your tax code.
Student loan repayments stack on top of income tax and NI. If you are in the 60% trap band with a Plan 2 loan, your effective marginal rate is 71%. With a postgraduate loan on top, it reaches 77%.
While you cannot avoid the repayment itself, you can check whether you are close to full repayment. If your remaining balance is small enough that you will clear it this year, overpaying before 5 April avoids unnecessary deductions from April's pay packet (SLC processing can lag by several months).
Equally important: if you have a Plan 2 loan with a large balance (£40,000+), do not make voluntary overpayments — the balance will likely be written off before you fully repay it. Our student loan guide explains the maths for each plan type.
If you are an experienced investor, the Enterprise Investment Scheme (EIS) and Seed EIS offer generous income tax relief:
EIS: 30% income tax relief on up to £1,000,000 invested. A £50,000 EIS investment reduces your tax bill by £15,000. Gains are tax-free after 3 years. You can also carry back relief to the previous tax year.
SEIS: 50% income tax relief on up to £200,000 invested. A £20,000 SEIS investment saves £10,000 in tax.
These are high-risk investments in small companies and are not suitable for everyone. But for high earners already maxing out pension and ISA, they offer the most generous remaining tax reliefs. See our EIS/SEIS guide for details.
EIS and SEIS investments must be made before 5 April to claim relief in this tax year. However, you can also carry back EIS relief to 2024/25 if you have unused income tax liability from that year.
If you or your partner earns between £60,000 and £80,000, check whether a pension contribution before 5 April could reduce or eliminate the High Income Child Benefit Charge for this year.
Remember: the charge is based on the higher earner's adjusted net income for the full tax year. A lump-sum pension contribution made in March 2026 reduces your 2025/26 adjusted net income — potentially saving the full year's child benefit.
For a family with two children, eliminating the charge saves up to £2,251.60 per year. Combined with the 40% tax relief on the pension contribution itself, this can be extraordinarily efficient. Run the numbers with our tax calculator.
If you can only do a few things before 5 April, do them in this order:
1. Pension contributions — highest tax saving per pound, especially in the 60% trap or HICBC zone.
2. ISA funding — permanent tax-free shelter that compounds year after year.
3. CGT allowance — use it or lose it; Bed and ISA combines items 2 and 3.
4. Tax code check — free, takes 10 minutes, could recover hundreds.
5. Marriage allowance — free money if eligible, backdatable 4 years.
6. Gift Aid claims — claim higher-rate relief you may have missed.
Everything else (salary sacrifice, student loan review, EIS/SEIS) is important but can be set up for the new tax year if you run out of time.
5 April 2026 — 2025/26 tax year ends. Last day for ISA contributions, pension contributions, CGT crystallisations, and EIS/SEIS investments for this tax year.
6 April 2026 — 2026/27 tax year begins. All annual allowances reset.
31 July 2026 — Second payment on account for 2025/26 self-assessment (if applicable).
5 October 2026 — Deadline to register for self-assessment for 2025/26 (if not already registered and liable — e.g., due to HICBC or income over £150,000).
31 January 2027 — Self-assessment filing and payment deadline for 2025/26.