Plum Cash ISA

4.27%

interest rate

£20,000

maximum per year

4.0 ★★★★

by WInvest

Who is Plum?

Plum is a UK-focused finance app that helps users save, invest and manage money automatically with smart rules and tools. It combines saving features, investment options and budgeting functions in one mobile-first platform, making it easy to grow tax-free savings like Cash ISAs alongside other financial goals.

Pros and cons

Competitive variable interest rate that can be very high compared with many traditional banks (e.g., around 4.27% AER with an initial bonus) and may include bonus interest conditions
Easy access to your money–you can withdraw whenever you need it without penalty
Low minimum deposit (from as little as £1) and quick digital setup through the Plum app

Interest rate is variable and can change; bonus rates may only apply for a period or under certain conditions
It’s not a flexible ISA — withdrawing money affects your ISA allowance for the year
Being app-based, some users find mobile-only interaction and customer support limited compared with bank-based providers

What is a Cash ISA?

A Cash ISA is a savings account where all interest you earn is completely tax-free. Every UK resident aged 18 or over gets an annual ISA allowance at the start of each tax year. For the 2025/26 tax year (ending 5 April 2026), the allowance is £20,000, and from April 2027 it will reduce to £12,000. Cash ISAs come in different types, including easy-access accounts and fixed-term accounts.

What is an easy-access Cash ISA?

An easy-access Cash ISA allows you to withdraw your money whenever you need it, without paying any penalties. The interest rate is variable, so it can rise or fall over time. Some easy-access ISAs are also flexible, meaning withdrawn money can be replaced without affecting your allowance.

Who is Plum Cash ISA good for?

The Plum Cash ISA is ideal for savers who want tax-free interest with easy access and low barriers to entry, especially if you like managing money from your phone and appreciate automated saving tools. It suits people who want a highly competitive rate and the flexibility to withdraw funds when needed, but it may be less appealing if you prioritise flexible ISA features (where withdrawals don’t affect your allowance) or prefer traditional banking support.

WInvest Rating

4.0 ★★★★

Easy way to save money, but withdrawal times can be slow

I’ve been with Plum for 2.5 years. Fantastic way to save money, and super easy to invest if you’re overwhelmed by choice. I’ve earned a sizeable chunk of interest on my savings, which I can see at any time in their very user-friendly app. The only negative thing I can say is that the withdrawal times from pockets (let alone investments) can be a bit slow, taking a few working days at times and the money landing in my account very late in the evening. So if you’re not expecting to use Plum as a dire-emergency-fund, it’s all good. On the few occasions where I’ve had a problem with withdrawal times, the Plum team are very responsive to messages.

4.0 ★★★★

I’ve been using Plum for years now and even got my partner and some family and friends involved. It’s a very easy app to use, and to save. It has many options to add to your savings and can be as aggressive or easy as you need. Their customer service response is also really good when I’ve used it. 100% recommend.