The ISA deadline for the 2025/26 tax year is on 5th April 2026 at midnight. This is the final day UK savers and investors can use their annual ISA allowance before it resets for the new tax year on 6th April. Any contributions made after the deadline will count toward the 2026/27 allowance instead.
ISAs are popular because they allow your savings and investments to grow free from income tax, capital gains tax and dividend tax. However, the allowance is strictly “use it or lose it”, any unused allowance from the 2025/26 tax year cannot be carried forward.
For the 2025/26 tax year, adults aged 18 or over can contribute up to £20,000 across all ISA types combined. This includes Cash ISAs, Stocks & Shares ISAs, Lifetime ISAs, and Innovative Finance ISAs. Lifetime ISAs have their own annual limit of £4,000 (which counts toward the £20,000 total), while Junior ISAs have a separate allowance for children.
To make the most of the ISA deadline, it’s important not to leave contributions until the last minute. Payments must clear and be credited to your ISA account by 5th April, which can be an issue if you’re transferring funds or using cheques. If you hold multiple ISAs with different providers, it’s also worth checking your total contributions to avoid exceeding the annual limit.
Once the deadline passes, a new ISA allowance becomes available from 6th April 2026, but any unused allowance from the previous year is gone for good. Planning ahead and using as much of your allowance as possible before the deadline can significantly improve your long-term tax efficiency.
The ISA deadline on 5th April 2026 is a key date for anyone looking to protect their savings from tax and acting early can help you make the most of it.
Source: https://www.gov.uk/individual-savings-accounts
**Please note, this article is for general information purposes only. Always seek advice from a qualified financial adviser before taking action.**
