A new ISA is likely to appeal to customers due to the flexibility it provides.

Speaking as the company launched an 18-month fixed-rate ISA paying 3.15 per cent, Leeds Building Society's sales and marketing director Kim Rebecchi suggested it offers "an excellent home for savers looking to invest their [2011-2012] ISA allowance".

This will take effect from April 6th and Ms Rebecchi added the account provides savers with the option of accessing up to 25 per cent of their money without penalty, whenever they choose, something the organisation stated is "unusual" for fixed-rate products.

Customers can choose to invest a minimum of £1 or a maximum sum of £5,340 and will be able to benefit from interest paid on April 5th 2012 and when the ISA matures on October 31st 2012.

At present there are 67 branches of the Leeds Building Society, which has a history dating back to 1886.

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