Martin Lewis has warned people to check for an 'X' on their payslips.
The Money Saving Expert founder said that if you spot it then there is a chance you are on the wrong tax code. The warning came as he appeared on his ITV Money Show Live.
The finance guru answered a question from viewer Tina, who said she had been overtaxed and wanted to know if she was entitled to a rebate. She said: "I’m on a 16-hour contract, and last month, I did lots of overtime. I was put on the basic rate temporarily and overtaxed by more than £800."
