To not pay back my overpaid wages?

[MrsAngle]

Ok, well obviously I would BU to not pay it back....but...

I work part time, and (I'm going to round up the figures for this post) am paid £750 a month.

Last month my regular wages went into the bank, followed by another payment of £480. My wage slip (erroneously) said my hourly rate had gone up and they paid me over £1300 minus tax/NI
Wages person was away, and on return said it would be sorted out.

Yesterday I got my usual £750 in the bank, then another payment of £185. Apparently they were "supposed" to just pay me the £185, which would add to the extra they paid last month and "make it right".
Now, my employer is expecting me to pay back £750, but I think I should only pay back £185 + £480 (£665).

So, AIBU to not pay them?

You need to ask for a full breakdown of all of the amounts in question.

Essentially you need to know the difference between what you actually received after deductions and what you should’ve received. That what you repay.

The tax is for them to sort out.

Payroll software often has the option to ‘rollback’a period to recalculate a period which is what should be done in this scenario. Then payroll should be run again for the next period (correctly). That will show the correct amounts and deductions for the period.

It will then be obvious what you need to repay.

They need to send an adjustment to HMRC via their RTI software to account for tax and NI.

This is not complicated stuff and it sounds like the payroll person and accountant don’t quite have a grasp on what’s going on.