1 Year Fixed Rate ISA vs Cash ISA vs Open Access Cash ISA
What all three have in common
All three are cash ISAs. Your interest is tax-free, it doesn't touch your personal savings allowance, and what you pay in counts towards the same £20,000 allowance for the tax year.
The difference is what you give up, and what you get for it.
Where they differ
1 Year Fixed Rate ISA | Cash ISA | Open Access Cash ISA | |
Interest rate | Fixed for a year from when your money lands | Variable | Variable |
When interest is paid | On each Vault's access date | Monthly, on the first of the month | Monthly, on the first of the month |
Adding money | While a funding window is open | Any time | Any time |
Taking money out | A penalty charge applies before your access date | Any time | Any time |
Conditions on the rate | None once your money has landed | A lower rate applies if you make four or more withdrawals in a 12-month period, or if your balance is below £500 | A lower rate applies if your balance is below £500 |
Changing your mind | 14 days from opening to cancel | 30 days from when we receive your first contribution or transfer. | 30 days from when we receive your first contribution or transfer. |
The 1 Year Fixed Rate ISA is powered by Aldermore, which works differently from our other savings accounts. There's more on that in the FAQs.
What "powered by Aldermore" means
When each could fit
A fixed rate could fit money you've set aside for a year or more, where you'd rather know your return up front than watch a variable rate move.
A Cash ISA could fit money you want to keep growing while still being able to reach it, as long as you're not dipping in often.
An Open Access Cash ISA could fit money you may need at short notice, or that you're adding to regularly.
They aren't alternatives you have to choose between. Plenty of people hold more than one, with different money in each.
Can I have more than one cash ISA?
Yes. You can pay into more than one cash ISA in the same tax year, as long as what you pay in across all of them stays inside your £20,000 allowance for the 2026/27 tax year.
Moving money between them
You can move money from your Moneybox Simple Saver, Cash ISA, or Open Access Cash ISA into a 1 Year Fixed Rate ISA, as long as you've got a funding window open.