Compare the AER, which shows the yearly interest rate including compounding, rather than relying on the headline rate alone. Check whether the account is easy access, notice or fixed term, and look for withdrawal limits, minimum deposits, introductory bonuses and penalties for early access. Consider whether a cash ISA could suit you if you want tax-free interest, and check the provider’s protection under the Financial Services Compensation Scheme. You can use comparison tables, then verify the latest terms directly with the provider before applying.