ING Direct, the Dutch bank-owned savings provider, has written to thousands of customers to warn them that it will not be passing on the benefit of last month's rise in the Bank of England base rate.
ING, which won a major share of the savings market after an aggressive launch in the UK three years ago, said it believed it offered a "consistently good rate". The letter added: "On this occasion, this means we have made the decision to maintain our ING Direct Savings Account interest rate at 4.75 per cent."
The decision has surprised savings analysts, because ING has in the past been keen to maintain its position at or near the top of best-buy tables. Several of its closest rivals have chosen to increase their rates in recent weeks.
"ING's unexpected announcement has caused quite a stir," said Andrew Hagger of the personal finance analyst Moneyfacts. "While we could agree that a consistent and competitive approach is welcomed by many consumers, I wonder how the many loyal ING customers feel about missing out on an additional quarter per cent on their savings?"
Moneyfacts said that four in five savings-account providers had now passed on at least some of the 0.25 percentage point increase in base rates to customers.