Plum's 4.66% Cash ISA: Is It the Best Rate Before the ISA Deadline?

With ISA season in full swing, Plum has grabbed attention with a 4.66% interest rate on its Cash ISA. For savers scrambling to use their £20,000 allowance before 5 April, it looks like a strong contender. But is it genuinely the best option out there, or is there a catch?

Plum's Cash ISA pays 4.66% AER on balances, which sits comfortably above the average easy-access Cash ISA rate. The account is managed entirely through the Plum app, which also offers budgeting tools, round-ups, and investment options. There's no minimum deposit required, and your money is protected by the FSCS up to £85,000 — Plum partners with a UK-regulated bank to hold your deposits.

At 4.66%, Plum is competitive but not the absolute highest. Some fixed-rate Cash ISAs offer slightly more — but you lose access to your money for 1-2 years. Among easy-access options, Plum sits in the top tier alongside providers like Chip, Moneybox, and Trading 212. The key advantage is flexibility: you can withdraw without losing your rate, which matters if you're not sure you can lock funds away.

Plum's rate is variable, meaning it could drop after the ISA deadline rush. This is common — many providers boost rates to attract ISA season deposits, then quietly lower them a few months later. It's worth checking back in June or July to see if the rate has held up. Also, Plum's premium features (like higher investment limits) require a paid subscription, so make sure the free tier gives you everything you need.

If you want a solid easy-access Cash ISA with a top-tier rate and a decent app experience, Plum is a genuinely good choice for the 2025/26 tax year. Just don't assume the 4.66% will last forever — variable rates move with the market. Use it to park your ISA allowance now, and revisit in a few months to make sure you're still getting a fair deal.