Police are investigating after Kent-based Kennington Garage was targeted by thieves.
The criminals smashed their way through a double-glazed window to get into the building and took the till along with a box of chocolates.
Owner, Edward Crouch said: “It is really annoying but they only got about three pounds and a box of Matchmakers a customer left us.
“We don’t leave notes in the till and there was only a little bit of change left in it.
“We haven’t had anything like this happen for years – I am very surprised because we are alarmed and it did go off.
“They must have got in and out very quickly.”