Sometimes a tax code may have two letters and no numbers or be another combination:
This code is commonly used where it is an employee’s second job and the all their personal allowances are used in the first/main job. All income earned under a BR tax code will be taxed at basic rate.
An employee with this code has all their income taxed at the higher rate of tax. This is also commonly used with a second employment, where the first job uses up all the personal allowances and income taxable at the basic rate of tax.
An employee with this code has no tax deducted at all from their pay.
T at the end of a tax code indicates “temporary”, specifically that there may be items under review by HMRC.