Cash ISA Transfers: How to Switch Without Losing Tax Protection

Moving a Cash ISA to a better-paying provider is routine. But withdrawing the money yourself can turn a transfer of existing savings into a new subscription that uses your annual allowance. Flexible ISAs have replacement exceptions, so the account terms matter.

Understanding why that fails, and what to do instead, is the whole of this guide.

Use the provider transfer process to move a Cash ISA. Withdrawing from a non-flexible ISA and re-depositing normally counts as a new subscription against this year's £20,000 allowance. Flexible ISA replacement rules can change that result, but are not a substitute for checking how the money should move.

Instead, apply to the new provider and complete their ISA transfer form. They collect the money from your old provider, the funds never leave the ISA wrapper, and none of your allowance is used.

Never withdraw money from an ISA in order to move it.

Money inside an ISA benefits from its tax protection. After a withdrawal from a non-flexible ISA, paying the money into a new ISA normally counts as a new subscription, which means:

• It consumes part of your current-year £20,000 ISA allowance
• If the amount exceeds your remaining allowance, the excess cannot be subscribed in that tax year
• Years of accumulated tax-free savings can be stripped of protection in a single afternoon

Someone with £60,000 built up across several years who withdraws it from a non-flexible ISA can generally subscribe at most £20,000 that tax year, assuming none of the allowance has already been used. The remaining £40,000 sits outside the wrapper unless another valid route applies. Future annual allowances may shelter it gradually, but that does not restore the original transfer treatment.

A flexible ISA has different rules. Withdrawn current-year subscriptions can restore net subscription capacity, while withdrawn previous-year funds generally need to return to the same account during the tax year of withdrawal. Our flexible ISA withdrawal guide explains both cases.

The correct route is a transfer, where the money moves provider to provider without ever leaving the ISA wrapper. A transfer does not count as a subscription and does not touch your allowance.

The process is initiated with the new provider, not the old one. This is counterintuitive and is where people go wrong.

1. Open or select the receiving ISA. Check it accepts transfers in — not all do, and some accept transfers only at account opening.
2. Complete the receiving provider's ISA transfer form. You supply your existing provider's details, the account number, and how much you want to move.
3. The new provider contacts the old one and requests the transfer under the ISA Regulations.
4. The old provider releases the funds and the receiving provider credits your account.

You do not need to contact your existing provider yourself, and you should not close the old account first. Closing it before the transfer request arrives is functionally the same as withdrawing.

GOV.UK says Cash ISA to Cash ISA transfers should take no longer than 15 working days, and other ISA transfers no longer than 30 calendar days. Transfers involving investments can need time for assets to be sold or re-registered. GOV.UK: ISA transfer timescales.

Interest treatment during the transfer varies by provider. Some pay interest up to the transfer date; some have a gap where money is in transit and earning nothing. Over a few days the amount is small, but check if you are moving a large balance.

If a transfer stalls well beyond the expected window, raise it with the receiving provider first, since they are managing the request, then complain formally if it is not resolved. Persistent delays can be escalated to the Financial Ombudsman Service.

The ISA Regulations treat these differently, and it affects how much flexibility you have.

Previous tax years' money can be transferred in whole or in part. You can move £10,000 of a £40,000 balance built up over several years and leave the remainder where it is.

Current tax year subscriptions could once only be moved as a single block. That changed on 6 April 2024: partial transfers of current-year subscriptions are now permitted under the ISA Regulations.

The catch is that permitted is not the same as available. Providers are not obliged to offer partial transfers of current-year money, or to accept them. Where a provider does offer it, that will be set out in the account terms and conditions. So a saver wanting to move only part of this year's subscription may still be told no — but by the provider's policy, not by the rules.

Either way, be explicit with the receiving provider about which portion is current-year and which is from previous years. Providers ask, and getting it wrong causes the transfer to be rejected or repaired later.

You are not limited to Cash ISA to Cash ISA. You can transfer:

• Cash ISA to Stocks and Shares ISA
• Stocks and Shares ISA to Cash ISA
• Either into a Lifetime ISA, subject to the £4,000 annual LISA cap
• Innovative Finance ISA to other types

Transferring into a Lifetime ISA is the one to think carefully about, because money entering a LISA becomes subject to the 25% withdrawal charge if taken out other than for a qualifying first home purchase, after age 60, or on terminal illness grounds. Our guide on moving a Lifetime ISA between providers covers LISA-to-LISA transfers, which do not trigger the charge.

Withdrawing to "move it yourself." This can turn existing ISA money into a new subscription, subject to the flexible-account exceptions above.

Closing the old account first. Same effect as withdrawing.

Assuming the new account accepts transfers. Many headline-rate accounts are for new money only. Confirm before opening.

Missing a fixed-rate exit penalty. Transferring out of a fixed-rate ISA before maturity usually triggers an interest penalty under the account terms, exactly as breaking a fixed-rate bond early does. The transfer is permitted; the penalty still applies.

Assuming you can split current-year money. Partial transfers of current-year subscriptions have been permitted since 6 April 2024, but no provider has to offer them. Check the terms before planning around it rather than after.

Chasing a rate that has already gone. Check the receiving rate is still available to transfers in, not just to new subscriptions.

Looking for more on this topic? Browse all our savings guides.

If your fixed deal is ending, see cash ISA maturity and reinvestment for the distinction between renewing existing savings and adding new money.

This guide is based on UK primary legislation, regulator handbooks, and official guidance. The following sources cover the rules described above:

• Individual Savings Account Regulations 1998
• GOV.UK: transferring your ISA
• HMRC: flexible ISA subscriptions
• FCA Handbook — BCOBS (Banking: Conduct of Business)
• Financial Ombudsman Service

Free, impartial money guidance is available from MoneyHelper, the government-backed service run by the Money and Pensions Service.

Related: ISA Allowance: How the £20,000 Limit Works | Moving a Lifetime ISA Between Providers | All savings guides.