Building societies paid savers an extra £2.1bn in interest in 2025 compared with average rates offered by the UK’s largest banks, Moneyfacts has found.

As part of UK Savings Week, the financial product price comparison site revealed that a £10,000 balance held for one year would earn £422 with the average top-rate building society account.

This compares to £116 with the average big bank easy access account.

After accounting for inflation, a £10,000 balance in an average big bank account would lose value in real terms, while building societies can help savers protect their cash.

Personal finance analyst at Moneyfacts, Caitlyn Eastell, stated: "Savers could be missing out on hundreds of pounds simply by leaving their cash in a lower-paying account. UK Savings Week is a great opportunity for savers to review where their money is held, because the difference between savings rates can have a significant impact on returns over time. In 2025, building societies paid savers an additional £2.1 billion in interest compared with the average rate offered by the largest banks, highlighting the important role they play in driving competition.

"Building societies continue to play an important role in the savings market, frequently offering competitive returns and rewarding savers that are proactive with their cash. Just because a balance is growing on paper, it doesn’t always mean savers are better off in real terms. To avoid missing out, savers should compare rates regularly across the whole of market, and switch to a more competitive deal if they find their hard-earned cash isn’t being rewarded."

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