For years, one of the most common myths in UK personal finance went like this: you can only pay into one cash ISA per tax year. Open a second and you risk breaking HMRC rules, losing your tax-free wrapper, or worse. That myth stopped countless savers from chasing better rates mid-year, and it kept billions of pounds sitting in uncompetitive accounts.
It is no longer true. Since 6 April 2024, you can pay into as many cash ISAs as you like in the same tax year, across as many providers as you choose, as long as your total deposits stay within the £20,000 annual ISA allowance. This single rule change has quietly transformed the way smart savers can manage their money.
But there is more to it than simply opening a second account. The rules around how the allowance works, how transfers function, and what is coming in April 2027 all matter if you want to get this right. This guide explains everything clearly, without the jargon.
The Old Rule: One ISA Per Type Per Year
Under the rules that applied up to and including the 2023-24 tax year, you were limited to paying into one ISA of each type in any given tax year. In practice, that meant one cash ISA, one stocks and shares ISA, one innovative finance ISA, and one Lifetime ISA — no doubling up.
This caused real problems. Suppose you opened a one-year fixed-rate cash ISA in April 2023 and locked in a 4% rate. By December 2023, rates had jumped to 5.5%. You could not open a second cash ISA to capture the higher rate — your only option was to transfer the whole balance (and lose the fixed-rate terms) or sit on your hands and watch the opportunity pass.
The rule was designed for simplicity, but in practice it penalised proactive savers and reduced competition between providers. The Government recognised this and changed it.
The New Rule: Multiple ISAs of the Same Type Allowed
From 6 April 2024, the restriction on paying into multiple ISAs of the same type in one tax year was removed. You can now open and pay into several cash ISAs simultaneously within a single tax year, provided your combined deposits across all of them do not breach your £20,000 annual allowance.
This applies to:
- Cash ISAs — including easy-access, notice, and fixed-rate cash ISAs
- Stocks and shares ISAs
- Innovative finance ISAs
The Lifetime ISA and Junior ISA remain restricted — you can still only pay into one of each per tax year.
It is also worth checking individual provider terms. Some providers do not allow you to hold two accounts with them at the same time, even if HMRC rules permit it. The rule change removes the legal barrier — it does not force every bank or building society to offer multiple accounts to the same customer.
How the £20,000 Allowance Works Across Multiple ISAs
The £20,000 annual ISA allowance has not changed. What has changed is how flexibly you can use it. You can split that £20,000 however you like across any combination of ISA types — and now across multiple accounts of the same type too.
Here is a simple example of how you might split the allowance across three cash ISAs in 2026-27:
| ISA Account | Provider | Type | Amount Deposited |
|---|---|---|---|
| Cash ISA 1 | Provider A | Easy Access | £6,000 |
| Cash ISA 2 | Provider B | 1-Year Fixed Rate | £8,000 |
| Cash ISA 3 | Provider C | Notice (90-day) | £6,000 |
| Total | £20,000 |
All three accounts sit within the £20,000 limit, all earn interest tax-free, and you have not broken any rules. The flexibility lets you match each pot to its purpose: instant access for emergencies, a fixed rate for money you will not need for a year, and a notice account earning a premium over easy access.
You can check current rates across all three account types on our best cash ISA rates page and understand the full allowance picture in our ISA allowance 2026 guide.
Partial Transfers: The Other Big Change
Alongside the multiple-ISA rule, the April 2024 reforms also introduced partial transfers of current-year ISA subscriptions. Under the old rules, if you had paid money into a cash ISA during the current tax year and wanted to move some of it to a better-rate provider, you had to transfer the whole balance or none at all.
You can now transfer just part of your current-year contributions to a new provider, while leaving the rest where it is. This works alongside the multiple-ISA rule to give you much greater mid-year flexibility.
A few important caveats apply:
- Not every provider is obliged to accept partial transfers — always check before initiating one
- You must use the formal ISA transfer process; withdrawing the money and depositing it elsewhere does not count and will eat into your remaining allowance
- Previous years’ ISA balances can always be transferred in full or in part without affecting your current-year allowance
The practical upshot: if rates rise sharply mid-year, you no longer have to choose between loyalty and a better deal.
FSCS Protection: Why Spreading Across Providers Makes Sense
One of the most practical reasons to hold multiple cash ISAs with different providers is FSCS protection. The Financial Services Compensation Scheme protects savings up to £120,000 per person, per authorised institution — a limit that rose from £85,000 in December 2025.
That limit applies per institution, not per account. If you have £130,000 in cash ISAs all with the same bank, only £120,000 is guaranteed if that institution fails. The extra £10,000 is at risk. Split that across two banks and every penny is covered.
One important nuance: some banks operate under the same banking licence despite trading under different names. For example, two brands owned by the same parent company may share one FSCS limit between them. Always check which banking licence a provider operates under before assuming you have separate protection.
Now that you can legally hold multiple cash ISAs, spreading large balances across providers is a straightforward and sensible way to stay inside the protection limit at every institution.
Rates change fast — are your ISAs keeping up?
With multiple cash ISAs now allowed, it is easier than ever to switch part of your savings to a better rate without losing your tax-free wrapper. Check the latest rates, read our guides, and take control of your savings at GetSmartSaver.
Explore GetSmartSaver →The 2027 Cash ISA Allowance Cut: What You Need to Know Now
The most significant cloud on the horizon for cash ISA savers is the 2027 allowance cut. Announced in the Autumn Budget 2025 and confirmed for 6 April 2027, the annual cash ISA limit for savers under 65 will fall from £20,000 to £12,000.
The key points you need to understand:
- Under-65s: from April 2027, you can only deposit up to £12,000 per year into cash ISAs
- Aged 65 and over: your cash ISA limit remains at £20,000 — at least initially, according to current Government statements
- The overall total ISA allowance stays at £20,000 — under-65s can still use the remaining £8,000 in stocks and shares ISAs or other ISA types
- Existing balances are not affected — money already held in your cash ISA continues to grow tax-free with no cap on the balance you can hold
The Government’s stated aim is to nudge younger savers towards investing rather than holding large sums in cash. Whether you agree with that logic or not, the practical implication is clear: if you want to maximise your cash ISA contributions, you have two full tax years — 2025-26 and 2026-27 — to use the full £20,000 cash ISA limit before the lower cap kicks in.
We cover this change in full detail in our dedicated article: 2027 Cash ISA Rule Change — Everything You Need to Know.
Practical Strategies for Using Multiple Cash ISAs
So how should you actually use these new rules to your advantage? Here are four approaches that make sense for most savers:
1. Ladder your fixed-rate ISAs. Rather than locking all your cash ISA allowance into one fixed-rate deal for one year, spread it across two or three fixed-rate ISAs maturing at different times. This way you never have your entire ISA balance locked away when rates move, and you always have some cash ISA money becoming available.
2. Keep an easy-access ISA for your emergency pot. Put a portion of your allowance in an easy-access cash ISA and the rest in higher-rate fixed or notice accounts. Your emergency fund stays accessible and tax-free, without dragging down the rate on the rest.
3. Chase rates without losing your wrapper. If a better easy-access rate becomes available mid-year, you can open a new cash ISA at the better rate and continue depositing new money there, while your existing account continues to earn on its existing balance. You are not trapped.
4. Spread large balances for FSCS safety. If your combined ISA savings exceed £120,000, splitting across institutions ensures every pound is covered. With multiple cash ISAs now permitted, this is easy to arrange without any tax or allowance penalty.
5. Maximise the £20,000 allowance before 2027 if you are under 65. With just two tax years remaining before the cash ISA limit for under-65s drops to £12,000, depositing the full £20,000 in both 2025-26 and 2026-27 adds an extra £16,000 of tax-sheltered cash capacity compared with waiting until 2027. Existing balances are protected — but the annual window to add more cash at scale will close.
Frequently Asked Questions
Can I open two cash ISAs with the same bank?
HMRC rules no longer prevent it, but individual banks set their own terms. Most will allow you to hold different types of cash ISA with them (for example, one easy access and one fixed rate), but some may restrict you to one cash ISA per customer. Always check before applying. When it comes to FSCS protection, two ISAs held with the same institution share a single £120,000 protection limit — not two separate limits.
What happens if I accidentally pay in more than £20,000 across my ISAs?
HMRC will contact you if you breach the annual limit. Typically you will be asked to remove the excess and pay tax on any interest earned on it. Most providers have systems to prevent this, but the responsibility ultimately sits with you. Keep a running total if you have accounts with multiple providers, because each provider only knows about its own accounts.
Does the 2027 cash ISA limit affect money already in my ISA?
No. The £12,000 limit (for under-65s) applies only to new contributions from 6 April 2027 onwards. Whatever you have already built up in cash ISAs — whether that is £5,000 or £500,000 — continues to sit in the tax-free wrapper with no restrictions. The cut only affects how much new money you can add each tax year.
Do I need to tell HMRC about all my cash ISAs?
No separate declaration is required. Each ISA provider reports your subscription to HMRC directly. As long as your total deposits across all ISAs stay within the annual limit, no further action is needed on your part. You do not need to include ISA interest or gains on a self-assessment tax return.
Can I transfer a cash ISA to a stocks and shares ISA?
Yes. You can transfer a cash ISA to a stocks and shares ISA without it counting against your annual allowance, provided you use the formal ISA transfer process. Transfers between ISA types have always been permitted. This might become a more common choice for under-65s from 2027, when the cash ISA deposit limit falls — transferring existing cash ISA balances to a stocks and shares ISA carries no cap on the amount that can be transferred.
This article is for general information only and does not constitute financial advice. ISA rules and allowances are based on information available as of June 2026. Tax treatment depends on individual circumstances and may change. Always check the latest rules at gov.uk or consult a qualified financial adviser before making decisions about your savings.