Which form details how much money an employer has already withheld for taxes? w-2 a-5 t-10 m-9?

w-2

Explanation:
w-2 is an abbreviation for "Official and Tax statement".
It is a type of IRS tax form.

This form is used by the US employers to report:
1- taxes held from employees
2- wages paid to employees

Hope this helps :)

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