Our savings picks: This is Money's five favourite best buy cash Isas for 2015
Every little helps: Savings rates might be low but at least an Isa means interest is tax-free
Our savings correspondent Lee Boyce picks his five favourite cash Isas for savers in 2015 - essential reading to help you choose a top savings account for your money.
This page is kept up-to-date throughout the year - bookmark it for the very latest developments.
How an Isa works and why you should have one
Each year in April, savers are given a fresh Isa allowance that qualifies for tax-free interest.
For the 2015-16 financial year - which began on 6 April 2015 - the limit is set at £15,240, all of which can go into a cash Isa, after an announcement in the 2014 Budget.
And you can also transfer Isa money whichever way you wish between an investment account to savings account, whereas previously you could only shift it from saving to investments.
Although cash Isas don't currently offer fantastic rates, it is still worthwhile opening one to shield money away from the taxman.
Read This is Money editor Simon Lambert explain how to use a New Isa to boost returns.
Isa rules state you can only contribute to one Isa per tax year.
You can also transfer an old Isa for better returns. Here's a quick guide to Isa saving.
It is possible to switch your current year's cash Isa if you move the entire amount, but it is far simpler to get your choice right in the first place.
Rates are low, but that just makes an Isa more important
Savers have been hit in recent years with low interest rates as banks and building societies fail to match tax-free Isa rates to standard accounts.
To those injuries was added the insult of the Funding for Lending scheme that pushed cheap cash through banks and building societies to borrowers and removed the incentive to offer decent savings rates.
This is now closed for lenders looking to gain more funds by increasing mortgage lending, but with plenty left in their pots they have little incentive to offer good rates.
But low rates just make it even more important to shelter your interest from the taxman, which is what a cash Isa does.
In the 2015 Budget, George Osborne revealed that from April 2016, every basic-rate taxpayer will be able to earn £1,000 interest a year without having to pay tax. Higher-rate taxpayers will be able to earn £500 interest.
Read why Money Mail savings guru Sylvia Morris still believes using your cash Isa allowance is important despite the changes announced and Financial Mail on Sunday personal finance editor Jeff Prestridge also thinks the tax-free allowance is worth utilising.
Our five favourite Isas:
Virgin Money Defined Cash Isa - 1.51% [Full details]
- Facts: £1 to open
- Transfers in: Yes
- This is Money says: This Virgin Money cash Isa comes without a bonus, but to qualify for this top 1.51 per cent rate, you are limited to three withdrawals of the year. Fail to adhere to this, and the rate drops to 0.75 per cent. It accepts transfers in and is available online.
Shawbrook Bank One-Year Fixed Isa - 1.85% [Full details]
- Facts: Can be opened with £5,000
- Transfers in: Yes
- This is Money says: This is the top paying one year rate. It allows transfers in - the account is managed and opened online or over the telephone.
Leeds BS Three-Year Fixed Isa - 2.3% [Full details]
- Facts: Open with £100
- Transfers in: Yes
- This is Money says: This account offers the top rate fixed over three years and can be opened and operated online, in-branch and by post. It has a unique feature in the fact customers can withdraw up to 25 per cent of the money without penalty.
Coventry BS Two-Year Fixed Isa - 2.05% [Full details]
- Facts: Can be opened with £1
- Transfers in: Yes
- This is Money says: This two-year deal from Britain's third biggest building society accepts transfers in and can be opened with £1. The maturity date is November 2017, making it ever so slightly longer than two years. It can be operated in branch, by post, by telephone or online.
Post Office Online Isa - 1.51% [Full details]
- Facts: £100 to open
- Transfers in: Yes
- This is Money says: This easy-access cash Isa from the Post Office pays the same as the Virgin deal above - but comes with a bonus of 0.86 percentage points which drops away after 12 months. It can only be run online.
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