The West Bromwich Building Society's WeBSave Isa pays 2.88 per cent.
The good points
It is an online-only account, which should make it easy to manage, and it allows up to three withdrawals a year with no charge. The interest rate is slightly better than rival instant-access offerings from the likes of Santander and Halifax.
The bad points
The interest rate includes a bonus of 1.12 per cent up to 29 February 2012, leaving the account paying a paltry 1.76 per cent when the bonus ends. Make more than three withdrawals and you will be charged 60 days' interest. The minimum deposit is £1,000.
If you haven't yet used the 2010-11 Isa allowance you can shelter £5,100 away from tax demands before 6 April. Next year's allowance climbs to £5,340. You could consider this account but only if you ensure you switch when the bonus period ends next February. But there is no rush to sign up for this deal. There are likely to be several more competitive Isa deals launched in the run-up to the end of the tax year.