Not paying enough tax in new job - messy issue

Da_Crojanz

I started a new job on the 15th April, leaving my previous one on the 12th. I handed in a New Starter checklist to my new role when I arrived.

I got both salaries in today alongside both payslips, where I've been paid for 2 weeks by each job. I've barely paid any tax on either. Both salaries are above the 40-ish% thresholds (in Scotland so it doesn't work entirely the same) but I've only been taxed £368 from 3k in one job and £257 from 1.7k in the other. Student loan payments, which are usually about £200 a month, have not been taken at all. I have an M1 tax code in new job but standard code in old job.

I can gather this is a messy situation that came about due to the M1 code, it being the first month of the year and 2 salaries at 2 weeks each. I know I'll have to pay it back but what is the best process from my end and how can I resolve this? Assuming they recalculate next month I expect I'll get £100 or so docked form every payslip until it is paid back, but I'd rather just pay a lump sum back to them (and even that feels risky as i don't trust them to properly recalculate after I pay it back).

Dazed_and_C0nfused

If your original job has a cumulative code then simply hand your P45 to your new employer.

The correct tax will be calculated the first time they use this information.