How to Transfer a Cash ISA Without Losing Your Tax-Free Status

This is the one thing you absolutely must understand. If you withdraw money from a cash ISA and move it to a new ISA yourself, it counts as a new subscription — not a transfer. That means it uses up your £20,000 annual ISA allowance. If you've already contributed this tax year, or your old ISA holds more than £20,000 from previous years, some of that cash can never go back inside an ISA wrapper.

The official GOV.UK guidance is unambiguous: "If you withdraw the money without doing this, you will not be able to reinvest that part of your tax-free allowance again."

Here's a concrete example. Say you've built up £35,000 across several old cash ISAs over the past decade. You withdraw the lot, planning to open a new ISA. Your annual allowance is £20,000. You can only put £20,000 back in this tax year. The remaining £15,000 permanently loses its tax-free status. At a 4% interest rate, that's £600 a year of interest that's now taxable — costing a higher-rate taxpayer £240 annually, compounding every year.

The correct method: contact the new provider, fill in an ISA transfer form, and let them handle the move. Your money stays inside the ISA wrapper throughout.

Step 1: Check your current rate. Log into your existing ISA provider and find the current interest rate. If it's below 4%, you should transfer. Many banks move matured fixed ISAs onto default rates as low as 0.25%.

Step 2: Choose a new provider. The best easy-access cash ISAs accepting transfers include Moneybox at 4.26% AER and Plum at 4.02% AER. For fixed rates, Tandem Bank accepts transfers at 4.22% (one-year) and 4.21% (two-year). Coventry Building Society offers 4.21% (one-year) with online, app, and branch access. For a full rundown of current rates, see our fixed-rate cash ISA guide.

Step 3: Open the new account and request the transfer. When you apply for the new ISA, there's usually a checkbox or section asking whether you want to transfer existing ISAs. Tick it and provide your old ISA details — provider name, account number, sort code. The new provider sends a transfer instruction to the old one.

Step 4: Wait. Cash ISA-to-cash ISA transfers should complete within 15 working days. Transfers involving stocks and shares ISAs take up to 30 calendar days. Your old provider must release the funds within that window.

Step 5: Verify. Check that the full balance has arrived and that interest is accruing at the advertised rate. If the transfer takes longer than 15 working days, complain to your provider. If they don't resolve it, escalate to the Financial Ombudsman Service — it's free.

That's it. No branch visits required for most providers. The entire process can be initiated from your phone in under ten minutes.

Not all ISAs accept transfers in, and the ones that do sometimes offer lower rates for transferred money versus new deposits. This matters.

Accept transfers at full rate:

• Tandem Bank — 4.22% one-year fix, 4.21% two-year fix (app-only)
• Coventry Building Society — 4.21% one-year fix (online/app/branch)
• Furness Building Society — 4.20% two-year fix, 4.30% five-year fix
• Moneybox — 4.26% easy-access (limit: 3 penalty-free withdrawals per year)

Accept transfers at a lower rate:

• Trading212 — top for new money at 4.68%, but transfers earn a lower rate
• Chip — 4.66% for new money, 4.07% on transfers

Don't accept transfers:

• Investec 4.20% one-year fix — no transfers in
• Some Prosper accounts — no transfers

The lesson: always check whether the headline rate applies to transfers before committing. Tandem and Coventry BS are the standouts because they pay the same rate regardless of how the money arrives. For our complete ISA guide covering all ISA types, start there.

You don't have to transfer everything. Partial ISA transfers have always been allowed — you can move a portion of an old ISA to a new provider while leaving the rest where it is.

Since 6 April 2024, you can also open and pay into multiple cash ISAs in the same tax year. Before that change, you could only subscribe to one cash ISA per year (though you could hold old ones from previous years). This opens up useful strategies:

• Split new contributions: Put £10,000 in a one-year fix for certainty and £10,000 in easy-access for flexibility. Both inside the ISA wrapper.
• Consolidate old ISAs: Transfer five legacy ISAs paying 0.5-2% into a single high-paying account. Fewer accounts to track, better rate, same total protection.
• Ladder fixed terms: Spread money across one-year, two-year, and five-year fixes so a portion matures each year. This gives you regular opportunities to reinvest or access cash.

One constraint: don't push your combined savings with a single banking group above £120,000, which is the FSCS protection limit per person per institution. Check which brands share banking licences — for example, Tesco Bank shares FSCS protection with Barclays.

If you have ISAs scattered across three or four providers from the last decade, consolidation is particularly worthwhile. Our savings guide covers how to structure your broader cash holdings.

If your current ISA is a fixed-rate product that hasn't matured, transferring out triggers an early withdrawal penalty — typically 90 to 360 days' lost interest. Whether it's worth paying depends on the rate gap.

Example: You're eight months into a two-year fix at 2.80%. The penalty is 180 days' interest. On £15,000, that's £207.12 lost. But switching to a new two-year fix at 4.21% earns you an extra £211.50 per year. You break even in just under 12 months and come out ahead over the remaining term.

The formula is straightforward: calculate the penalty, calculate the extra interest per month from the new rate, and divide. If the break-even point falls well within the new term, transfer. If you've only got three months left on your current fix, just wait it out.

MoneySavingExpert's ISA switching calculator does this maths for you — input your current rate, remaining term, and the new rate to see whether switching makes financial sense.

The 2025/26 tax year ends on 5 April 2026. That gives you three weeks. Here's the priority order:

1. If you have unused ISA allowance: Open a new ISA and contribute before 5 April. You can't carry unused allowance forward — once it's gone, it's gone.
2. If you have old ISAs at poor rates: Initiate transfers now. The 15-working-day timeline means transfers started today should complete before 5 April — but don't leave it to the last week.
3. If you've already used your 2025/26 allowance: You can still transfer old ISAs at any time. Transfers don't use your annual allowance. This is separate from new subscriptions.

Don't confuse contributions with transfers. Subscribing £20,000 to a new ISA uses your allowance. Transferring £50,000 of old ISA savings to a better provider uses none of it.

For a broader view of how ISAs fit into your tax-year-end planning, read our article on making the most of your ISA allowance.

This article is for informational purposes only and does not constitute financial advice. You should seek independent financial advice before making any investment decisions.