A building society has launched a 'market-leading' Cash ISA, offering 4.56% interest. On Thursday (May 7), Skipton Building Society announced the launch of a new 18month fixedrate ISA.

The product offers the top rate currently on offer for an ISA over that duration - providing households with certainty while interest rates remain unpredictable. The account enables savers to protect up to £20,000 from tax in the current year, with the fixed rate applying throughout the entire 18-month period. Skipton confirmed the product is available to both new and existing customers and can be opened online, through its app, in branch or by telephone. However, the headline rate comes with conditions.

Withdrawals are prohibited during the term, and anyone closing the account prematurely will incur a penalty equal to 90 days' interest. The minimum deposit is £500, while balances can reach up to £1 million. Savers may also transfer in ISA funds from previous tax years.

Alex Sitaras, head of savings and partnership products at Skipton, said: "We've refreshed our 18-month fixed ISA, ensuring it remains firmly market-leading and available to both new and existing customers.

"It's a small change on paper, but a clear signal of our commitment to fairness and helping savers lock in strong, tax-free returns with confidence.

"In the current climate, where many households are under pressure and every pound matters, this means offering consistently competitive rates alongside clear, straightforward savings options.

"As well as delivering strong value and certainty, those who choose to save with Skipton benefit from access to free money guidance and regulated financial advice, helping them feel supported when managing their finances."

The launch arrives at a time of fierce rivalry among banks and building societies vying to attract deposits, as millions of savers seek better returns following years of disappointing rates.

However, experts caution that while fixed ISAs can provide certainty, they could leave savers trapped if rates climb - making flexibility just as crucial as the headline returns on offer.