Manager Steve Myers said the benefactor showed up at the Wal-Mart in Mechanicsburg before noon Monday with a cashier's check that barely covered the balances on about 100 accounts.
Monday was the deadline to pay off layaways. The store was about to cancel the accounts and refund the partial payments.
Instead, store associates called customers to give them the good news, although some suspected it was a joke.
The donor tells store officials people can refer to him as Santa B. He describes himself as a successful businessman.
Similar gestures include one last week at a Toys R Us in Bellingham, Massachusetts, where a woman paid $20,000 to cover 150 layaway accounts.