By MoneyWise UK Editorial Team | Last Updated: 25 September 2026 | Savings Accounts
The ISA allowance resets on 6 April every year, the first day of the new UK tax year. Your current £20,000 allowance for 2026/27 runs until 5 April 2027 and cannot be carried over. A fresh allowance starts on Tuesday 6 April 2027, which is also the day the new £12,000 cash ISA limit for under 65s begins.
The interactive checker loads here. If it does not appear, add up everything paid into your ISAs since 6 April: the total must stay within £20,000, with no more than £4,000 in a Lifetime ISA.
5 April 2027 is the last day to use your £20,000 2026/27 ISA allowance
Any allowance left unused after that date is lost for good. Source: GOV.UK.
When does the ISA allowance reset?
The ISA allowance resets on 6 April each year. ISA allowances follow the UK tax year, which runs from 6 April to 5 April the following year, so when does the ISA allowance reset is answered by the tax year calendar rather than the calendar year.
For the 2026/27 tax year, your £20,000 allowance runs from 6 April 2026 to Monday 5 April 2027. The next allowance starts on Tuesday 6 April 2027. Nothing resets on 1 January, and there is no grace period after 5 April.
The allowance works on a use it or lose it basis. If you pay £15,000 into ISAs by 5 April 2027, the remaining £5,000 of allowance is gone. On 6 April 2027 you start again with a new allowance, not £25,000.
| Tax year | Allowance starts | Last day to pay in | Overall ISA allowance |
|---|---|---|---|
| 2025/26 | 6 April 2025 | 5 April 2026 | £20,000 |
| 2026/27 (current) | 6 April 2026 | Monday 5 April 2027 | £20,000 |
| 2027/28 | Tuesday 6 April 2027 | 5 April 2028 | £20,000 (cash ISAs capped at £12,000 for under 65s) |
Why the tax year starts on 6 April
The odd date is a leftover from history. The tax year originally began on Lady Day, 25 March, one of the traditional quarter days. When Britain switched from the Julian to the Gregorian calendar in 1752, 11 days were dropped, and the tax year was moved to 5 April so that no tax was lost. A further adjustment in 1800 moved it to 6 April, where it has stayed ever since.
What resets and what does not
| Item | Resets on 6 April? | What happens |
|---|---|---|
| £20,000 adult ISA allowance | Yes | A fresh £20,000 starts. Unused allowance from the old year is lost. |
| £4,000 Lifetime ISA limit | Yes | A new £4,000 limit starts, counting towards the £20,000. |
| £9,000 Junior ISA limit | Yes | Each child gets a new £9,000 limit. |
| Money already in your ISAs | No | Balances stay in the ISA and keep their tax-free status. |
| Flexible ISA replacement window | Yes, it closes | Money withdrawn before 6 April can only be replaced without using allowance in the same tax year. |
| Number of ISAs you can pay into | Not affected | You can pay into several ISAs of the same type each year, but only one Lifetime ISA. |
A saver pays £20,000 into a flexible cash ISA in May 2026, then withdraws £5,000 in February 2027 for a home repair. If they put the £5,000 back before 5 April 2027, it does not use any extra allowance.
If they wait until 10 April 2027, the replacement counts as a new payment in the 2027/28 tax year. As they are under 65, it uses £5,000 of their £12,000 cash ISA limit for that year.
Beating the 5 April 2027 deadline
To use your 2026/27 allowance, the money needs to reach your ISA by 5 April 2027. A payment that leaves your bank account on 5 April but arrives on 6 April counts towards the next tax year. Practical steps:
- Check your provider’s cut-off. Some providers set their own deadline a few days before 5 April for new accounts, cheques or debit card payments. Their website usually lists it in March.
- Leave time for new accounts. Opening an ISA can involve identity checks. Starting a week or more early avoids missing the date.
- Use Faster Payments where possible. Bank transfers between UK accounts usually arrive within minutes, but check your own bank’s limits for large amounts.
- Transfers are different. Moving old ISA money between providers does not use the allowance and can happen at any time of year.
Only you can keep track of your total across different providers, because each provider only sees its own account. HMRC checks ISA payments after the tax year ends and can ask providers to remove any excess. GOV.UK sets out the ISA rules, and the checker above helps you add up this year’s payments.
What is different on 6 April 2027
The reset on 6 April 2027 is the first under the new ISA rules confirmed by the government. The overall allowance stays at £20,000, but:
- Under 65s can pay no more than £12,000 a year into cash ISAs. The other £8,000 can go into stocks and shares, innovative finance or Lifetime ISAs.
- People aged 65 or over can still pay up to £20,000 into cash ISAs. This applies from the start of the tax year in which they turn 65.
- Under 65s will no longer be able to transfer money from a stocks and shares ISA into a cash ISA.
- Money already held in cash ISAs is not affected.
This makes 2026/27 the last tax year in which under 65s can put a full £20,000 into cash ISAs. Our guide to the ISA allowance for 2026/27 covers the changes in more detail.
Paying in early or late in the tax year
Because the allowance resets on a fixed date, when you pay in during the year affects how much tax-free interest or growth you get in that year.
A higher-rate taxpayer has £20,000 in an ordinary savings account paying 4% AER and has already used their £500 Personal Savings Allowance on other savings. If they move it into a cash ISA paying the same rate on 6 April 2026, the full year of interest, about £800, is tax free.
If they wait until March 2027, most of that year’s interest is earned outside the ISA and taxed at 40%, costing around £300 in tax. Rates here are illustrative, and paying in early is only possible if the money is not needed elsewhere.
Paying in early is not right for everyone. Many people pay in monthly from their salary, which is fine as long as the total stays within the allowance. For stocks and shares ISAs, investing earlier gives money longer in the market, but values can fall as well as rise.
MoneyWise UK reviews publicly available UK guidance and trusted sources such as GOV.UK, HMRC, FCA and MoneyHelper. This guide is general information only, not personalised financial advice. Sources checked for this guide:
Some people believe unused ISA allowance rolls over into the next year, in the same way that unused pension annual allowance can sometimes be carried forward. It does not. The ISA allowance is lost if you do not use it by 5 April, and the new allowance on 6 April is always the standard amount.
- The ISA allowance resets on 6 April every year, at the start of the tax year.
- The 2026/27 £20,000 allowance ends on Monday 5 April 2027.
- Unused allowance cannot be carried over.
- Lifetime ISA (£4,000) and Junior ISA (£9,000) limits reset on the same day.
- Flexible ISA withdrawals must be replaced in the same tax year.
- From 6 April 2027, under 65s can pay up to £12,000 a year into cash ISAs.
Frequently Asked Questions
When does the ISA allowance reset?
The ISA allowance resets on 6 April every year. The current 2026/27 allowance ends on 5 April 2027 and the new 2027/28 allowance starts on 6 April 2027.
Can I carry over my unused ISA allowance?
No. Any part of your £20,000 allowance that you do not use by 5 April is lost. You get a new allowance on 6 April, not a larger one.
Can you put £20,000 into the same ISA every year?
Yes. You can pay up to your full allowance into the same ISA each tax year if the account accepts further payments. From 6 April 2027, under 65s can pay no more than £12,000 of that into cash ISAs.
Can I have £200,000 in a cash ISA?
Yes. There is no limit on how much an ISA can hold, only on how much you pay in each year. Cash savings are protected by the FSCS up to £120,000 per person, per banking licence, so large balances may be better spread across different banks.
Can I give my spouse money to put in their ISA?
Yes. Each adult has their own £20,000 ISA allowance. Gifts between spouses and civil partners are generally free of inheritance tax, so a couple can use up to £40,000 of allowance between them each tax year.
Does the Lifetime ISA allowance reset on the same day?
Yes. The £4,000 Lifetime ISA limit also resets on 6 April. It counts towards your overall £20,000 allowance, and you can only pay into one Lifetime ISA each tax year.
MoneyWise UK provides general information only. This is not financial advice. Figures are correct for the 2026/27 tax year as at the date shown and are based on official GOV.UK and HMRC guidance. Investments can fall as well as rise. Consider speaking to a regulated financial adviser before making major financial decisions.
This content is based on publicly available UK financial guidance and trusted sources such as GOV.UK, HMRC, FCA, and MoneyHelper. It is for informational purposes only and not financial advice. Rules and rates may change, so check official sources before making decisions.
