X M1 in tax code

brookspd74 wrote: »

Hi - I've just gone from a 131L to an 84LX tax code due to tax underpaid on a company car. I've had a read about cumulative and non cumulative but just wanted some confirmation.

I generally earn the same amount each month (barring 1 bonus month). I assume this X code will have little impact on my take home pay apart from in the month where I receive my bonus?

The tax you pay will increase compared to your old tax code but will be the same for each future payday when your gross is the same. The purpose here of the X or non-cumulative tax code is that it avoids the new code being back-dated to the start of the tax year and resulting in that extra back-dated tax being taken from your first payment after the code is operated.