ISA allowance 2026/27: making £20,000 work harder

Reviewed: July 2026Tax year: 2026/27Topic: Saving & ISAs

For the 2026/27 tax year (6 April 2026 to 5 April 2027) adults can put up to £20,000 into ISAs. Interest, dividends and capital gains inside an ISA are free of UK Income Tax and Capital Gains Tax. Use it or lose it — unused allowance does not roll forward.

One allowance, several ISA types

You can split the £20,000 across cash ISAs, stocks and shares ISAs, Innovative Finance ISAs and a Lifetime ISA (subject to LISA’s own £4,000 subscription cap, which counts towards the £20,000). You may open more than one ISA type in a year under current rules, but always confirm provider terms and GOV.UK updates before you subscribe.

Flexible cash ISAs may let you withdraw and replace money in the same tax year without eating extra allowance — hugely useful for emergency cash held in an ISA wrapper. Not every account is flexible; check before you treat it like a current account.

Cash vs stocks and shares

Cash ISAs suit near-term goals and emergency funds if the rate beats a taxable saver after your Personal Savings Allowance. Stocks and shares ISAs suit longer horizons (typically 5+ years) where you can tolerate ups and downs.

Interest outside an ISA may be covered by the Personal Savings Allowance (£1,000 basic rate, £500 higher rate for 2026/27), so a taxable easy-access account can still be fine for modest balances. Larger cash piles usually belong in an ISA once PSA headroom is tight.

Timing: do not leave it to 5 April

Providers need time to process applications and transfers. Last-minute bank holidays and verification checks strand people with unused allowance. If you invest a lump sum, consider whether pound-cost averaging suits your risk tolerance — the allowance deadline is not a reason to panic-buy funds.

Transfers between ISAs do not normally restart the allowance clock the way new subscriptions do; follow the transfer process so you do not withdraw and repay manually (which can waste allowance).

How this sits with other 2026/27 figures

Your Personal Allowance remains £12,570. Marriage Allowance can still transfer a slice of unused personal allowance between spouses or civil partners (worth up to about £252 in tax). Help to Save and Lifetime ISA bonuses are separate schemes with their own rules — they do not increase the £20,000 ISA cap, though LISA subscriptions count towards it.

Worked example: splitting £20,000

Step-by-step checklist

• Confirm how much ISA allowance you have already used this tax year
• Decide which goals need cash vs invested ISAs
• Check whether your cash ISA is flexible before withdrawing
• Transfer existing ISAs properly instead of withdrawing and restating
• Diariise a February review so you are not rushing in April
• Compare rates and fund charges — tax-free does not mean fee-free
• Keep proof of subscriptions for your own records

Common mistakes

• Assuming unused ISA allowance rolls into next year
• Withdrawing to move providers instead of using an ISA transfer
• Maxing a LISA without keeping emergency cash accessible elsewhere
• Chasing a headline rate without reading withdrawal limits

When to get regulated help

Official ISA rules live on GOV.UK. For choosing cash vs investing and risk basics, use MoneyHelper. Product sales should come from regulated providers; this site does not recommend specific accounts.

Frequently asked questions

Is the ISA allowance still £20,000 in 2026/27?

Yes — plan on a £20,000 adult ISA allowance for 2026/27 unless government policy changes mid-year. Always recheck GOV.UK.

Can I pay into more than one cash ISA?

Rules have eased in recent years, but provider terms differ. Confirm current GOV.UK guidance and each provider’s acceptance policy before you subscribe.

Do Junior ISAs use my £20,000?

No. Junior ISAs have a separate child allowance. Your adult £20,000 is yours alone.

What happens if I oversubscribe?

Providers and HMRC processes may reject or return excess. Keep a running total if you use multiple products.