How to compare savings accounts, fixed rates and cash ISAs

Katerina Galkina · EN · 07/10/2026

Start with when you need the money

Separate your savings into imminent expenses, an emergency reserve and money you genuinely will not need before a particular date. Write down the earliest likely withdrawal date for each portion. The highest advertised rate is less useful if you need access before the agreement ends.

MoneyHelper explains easy-access accounts ↗, but check the particular product’s withdrawal limits, minimum balance, temporary bonus, current-account requirement and access arrangements. The word “easy” is not a substitute for the terms.

Compare equivalent features

With fixed-rate savings bonds ↗, the rate is fixed for a term and early access may involve a penalty or be unavailable. Ask whether you can add money after opening, when interest is paid and what happens at maturity.

For each offer, record the AER, term, your proposed deposit, withdrawal conditions and interest over an equivalent period. For a regular saver, remember that deposits arrive gradually: the advertised annual rate does not mean the entire year’s deposits earn interest from day one. Distinguish deposit interest from an investment product’s projected return.

Calculate the tax position

A cash ISA is a tax wrapper, within which both easy-access and fixed-rate products can exist. Compare access conditions and the after-tax outcome rather than treating “ISA versus savings account” as two completely separate product types.

HMRC’s guidance ↗ sets the Personal Savings Allowance at £1,000 for basic-rate taxpayers, £500 for higher-rate taxpayers and £0 for additional-rate taxpayers. Other allowances may help people on low incomes. Interest from ordinary savings accounts is considered together. Your full taxable income for the tax year matters; the advertised bank rate cannot establish your tax liability by itself.

Check protection and keep the paperwork

Use the FSCS ↗ to check the institution and whether different brands share a banking licence. Standard protection for eligible deposits is currently £120,000 per person per authorised institution. Your other eligible accounts there count towards the same limit.

Save the product terms, opening date, bonus expiry and a maturity reminder. If moving an existing ISA, use the receiving provider’s ISA transfer process. Before committing, check the old product’s exit charges and ensure you can reach your emergency reserve without waiting for the fixed term to end.