It was a sickening, gut-wrenching moment when, one evening in October 2012, Sally Donaldson checked her bank account and realised she had made the silliest financial mistake of her life.
Two years earlier, hairdresser Sally had organised for her monthly pay, £1,000, to be transferred from her HSBC account to the joint account at Nationwide building society she shares with her husband. But on that October night, the mother of two discovered she had made a simple but calamitous error.
It's a mistake anyone can make. To transfer money online from one account to another, you simply tap in the recipient's name, their sort code and account number. But Sally had incorrectly typed in just one of the eight digits in the account number – and the money was sent to the wrong person.
What makes her story so extraordinary, though, is that she made the mistake in May 2010. Every month since – for more than two years – her pay was going into someone else's Nationwide account. And now, to her horror, Sally is discovering she has almost no chance of getting back a penny of the £26,650 transferred in error.
The recipient took the money, spent it, and is refusing to repay it. Nationwide says there is nothing it can do – and won't tell Sally who the recipient is because of data protection rules.
The fact she correctly entered her surname as the intended recipient at Nationwide, alongside the correct sort code, counted for nothing. When banks transfer money, they use only the sort code and account number – it turns out that account names are irrelevant.
Legally, Sally has every right to demand the money back – no one is entitled to keep money wrongly credited to their account. But getting it back is an altogether different matter.
Many people will sympathise with her over a silly mistake. But most will also wonder how she and her husband failed to notice a missing £1,000 every month. Indeed, Nationwide says it has never before come across a case of "mis-applied credit" that went on for so long.
The answer may lie in the widespread switch to paperless statements, where an account can only be viewed online. Sally did not see a bank statement from Nationwide for the entire period the money was going astray. She kept an eye on the balance when she took money out at the ATM, but that was about all, while her husband, who also paid his income into the account, sorted out most of the bills.
"By law, a person is not entitled to rely on another's mistake to keep money to which they were not entitled," a Nationwide spokesman says. But he adds: "The final payment transferred was recovered, but previous payments were no longer in the account. The recipient has been contacted and we have established she doesn't have the funds to repay."