I have been having issues with my tax coding for a while and was told that from the start of the financial year I would finally go onto the "standard" tax code.
When I got paid at the end of April I was still on my old code and so haven't paid the proper amount of tax on my wage.
Will I get a bill later on for the "missing" April tax or does it mean that my new code came into effect on this day and anything prior can be charged at the old rate??
Does a "M1" designation mean that your tax is calculated on what you earn each month rather than taking a yearly figure and dividing by 12?
My main worry is this - will the tax office want the tax money I *should* have paid in April, or will they treat that month as still being under the old code?