HMRC tax code updates

Ybe

Does HMRC tax code automatically update that month if your taxable income changes for whatever reason (for example a pay rise or if you were paid pro rata for your first month in a job to align with the employers payroll periods)? Or does it not update until the end of the tax year? 

TadleyBaggie

Generally tax codes remain the same when income increase. 

Dazed_and_C0nfused

Ybe said:

Does HMRC tax code automatically update that month if your taxable income changes for whatever reason (for example a pay rise or if you were paid pro rata for your first month in a job to align with the employers payroll periods)? Or does it not update until the end of the tax year? 

Not normally no.  But you can update your estimated (taxable) earnings from any job or pension you have via your Personal Tax Account.

If that means a revised tax code is needed them it will be issued to you and your employer*

*they only get the basic info i.e. code is 1050L, not how that has been calculated.

chrisbur

Your tax code tells you the amount of your earnings on which tax is not paid.  So unless something happens to change that figure (eg your personal allowance is reduced due to high earnings (Over £100000) your tax code will be correct (assuming it is correct to start with) all year. 
You mention  "if you were paid pro rata for your first month in a job"  Occasionally there are circumstances which can change your tax code when you change jobs, has this happened to you or was it just a for instance?