Weekly to monthly pay

eastcorkram

My tax code is 650L wk1. It's less than the normal code due to BIK.
Being changed from weekly pay to monthly this month. Do I need to do anything about the code? Or will it automatically change to an M1 code, or does it make no difference?

Dazed_and_C0nfused

Wk1 in that context means you are on a non cumulative code.

M1 is exactly the same, non cumulative rather than cumulative. 

It's often referred to as Wk1/Mth1.

There is nothing you need to do but you might want to post the last tax week number you expect to be paid and the first tax month (11?) you expect the monthly pay to be paid in as the first monthly payment might result in a little bit more tax than normal.

eastcorkram

Last weekly pay was wk 43.
Now due to get next pay 17thFeb, then 24th March . 

eastcorkram

......and a follow up question. 
If , after sal sac, my gross pay was 45,000. My pay goes up and down depending on overtime. So some weeks overtime might be £250. Some weeks just basic. Suppose I earnt the same every week and it also came to 45,000. Is the amount of tax paid per year the same, whether my code was 650L or 650L wk1? 

chrisbur

There would probably be a small difference which would vary a little depending on each individual month.
As an example on a cumulative code the tax would be £7856.00  at the month end and splitting the 45000 equally over the year the tax on non-cumulative would be £7853.52. So £2.48 difference.  
However HMRC will probably do a calculation which could result in a different figure and possibly some adjustment carried forward.