Glossary: Tax code
Used by an employer or pension provider to calculate the amount of tax to deduct from pay or pension. A tax code is usually made up of several numbers followed by a letter. If you replace the letter in your tax code with ‘9’ you will get the total amount of income you can earn in a year before paying tax, for example 747L would mean a person could earn up to £7,479 before paying tax. The wrong tax code could mean a person ends up paying too much or too little tax.