If an individual encounters personal income tax arrears on wages, he can make a complaint and report by calling 12366. 12366 is a complaint reporting telephone set up in State Taxation Administration of The People's Republic of China, which is specially used to deal with tax issues. After calling this number, you can explain in detail the situation of personal income tax on wages in arrears to the staff and provide relevant evidence and information. The staff will investigate and handle the case according to the situation, and protect the legitimate rights and interests of the whistleblower.