While instant-access cash ISAs are often the best option for savers looking for a flexible savings option, for those wishing to invest a lump sum a fixed-rate ISA is often the best bet as you could get a slightly better interest rate.
The financial arm of Marks & Spencer, M&S Bank, is offering a one-year cash ISA paying 1.85% with a minimum deposit of £500, but, as with any fixed-term bond, you can't make further contributions.
If you haven't used up your ISA allowance for the tax year already, you can put up to £5,640 in the account and with the interest rate fixed for the year, you will receive your return once the 12 months are up.
During the term you cannot make a partial withdrawal and there is a penalty charge of £50 if you withdraw the whole amount, so it is worth making absolutely sure you will not need to touch the money for a year.
The M&S account is available to open online, by phone and post, and can be accessed by phone and post. The account also allows transfers-in from older ISAs you might have.
M&S provides more fixed-rate alternatives if you're happy to lock your savings away for longer. The bank offers a two-year account paying 1.95% interest and a three-year account paying 2.05%.
Go to bank.marksandspencer.com for more information or call 0808 002 2222.