Your Cash ISA earns interest daily in the background, based on your cleared balance.
Your basic interest amount is paid into your Cash ISA monthly, on the first day of the month.
If you’re eligible for Plum bonus interest, it is paid into your account on the last working day of the month after the bonus rate period ends.
Before 1 September 2025: Basic interest was paid on the last working day of the following month.
Plum Bonus Eligibility
For Cash ISA accounts that were activated before October 30, 2025, the bonus rate for transfers from other providers is not applicable.
For Cash ISA accounts that were activated on/after October 30, 2025, the bonus rate for transfers from other providers is applicable and depends on the date of activation. For more details, you can check here.
In case of a transfer out of your Cash ISA to a different provider (either full or partial), the bonus will be lost unless it has already been credited to your account.
Important to know
Rates vary depending on when you opened your Cash ISA.
Plum uses the gross rate to calculate your interest daily.
The Annual Equivalent Rate (AER) stands for Annual Equivalent Rate, a measure of interest earned on a savings account over a year, including the effects of compounding interest.
We’ll always let you know in advance of any interest rate reductions.