ISA Allowance: How Much You Can Pay In, Splitting It, and the New Cash ISA Limit

The ISA allowance is the most you can pay into ISAs in one tax year. It’s a single allowance shared across all your ISAs, not one for each account.

The allowance for 2026/27

• You can pay in up to £20,000 each tax year, which runs from 6 April to 5 April.
• You can split it across several ISAs, including more than one ISA of the same type in the same year.
• You can pay into only one Lifetime ISA a tax year, up to £4,000, and that counts towards the allowance.
• You must be 18 or over and resident in the UK (or a Crown servant or member of the armed forces overseas, or their spouse or civil partner).
• An ISA is in one person's name: you can't hold one jointly.
• Interest, income and gains in an ISA are tax-free, and you don't declare them on a tax return.
• Moving money between ISAs with an ISA transfer doesn't count as paying in, so it doesn't use any of this year's allowance.
• Money already in your ISAs stays tax-free after the tax year ends.

Splitting it

You can pay the whole £20,000 into one ISA, or spread it however you like. GOV.UK’s own examples of a year’s payments:

The allowance counts what you pay in, not what the account is worth: interest and growth don’t use it up. With most ISAs, taking money out doesn’t give you the allowance back; with a flexible ISA you can put back what you took out in the same tax year.

More than one ISA

You can pay into several ISAs of the same type in the same tax year, for example two cash ISAs with different banks, as long as the total stays within the allowance. You can pay into only one Lifetime ISA a tax year. A Junior ISA is the child’s, with its own £9,000 limit, and doesn’t use your allowance (Junior ISAs).

ISA accounts from past years stay open and tax-free; you don’t have to pay into them again, and you can move them with a transfer, which doesn’t count towards this year’s allowance.

The 5 April deadline

Each allowance runs from 6 April to 5 April and can’t be carried over, so anything you don’t use by 5 April is gone. If you’re using the allowance near the end of the tax year, check your provider’s cut-off for payments and new applications, and leave time for the money to arrive before 5 April.

The cash ISA limit from 6 April 2027

• If you're under 65, you can put at most £12,000 a tax year into cash ISAs.
• The overall ISA allowance stays at £20,000, so the rest can go into other types of ISA.
• People aged 65 or over can still put up to £20,000 a year into cash ISAs.
• Transfers from stocks and shares ISAs and innovative finance ISAs into cash ISAs are restricted.
• Interest paid on cash held inside a stocks and shares or innovative finance ISA has a flat 22% charge.
• There are also new rules on money market funds held in stocks and shares ISAs.

In practice, if you’re under 65 and want to use the whole £20,000 from 2027/28, at least £8,000 of it will need to go into a stocks and shares, innovative finance or Lifetime ISA. The government estimates that 22% of cash ISA savers under 65 paid in more than £12,000 in 2022/23. Money already in cash ISAs isn’t affected: the limit applies to new payments in.

If you pay in too much

If you go over the allowance, the extra isn’t a valid ISA payment. It’s removed, and any tax relief on it is lost: see what happens if you go over the ISA limit.

Related guides

• ISAs guide: the ISA types, the allowance and the main choices in one place
• Cash ISA rates: average rates now, and cash ISA or savings account
• ISA transfers: moving an ISA without using allowance
• Inheriting an ISA: the extra allowance for a surviving spouse or civil partner