How to write an overpaid commission to employee and ask him to return.

If your making a correction then just identify what the problem was and the resolution. Just make sure your not overstepping what you intend to do. Depending on the amount you may need to split it up rather then take it back at one time.

You also need to tell them well in advance before you take the money from them.

Hello w:

Dear commission sales person:

We've discovered a discrepancy in your commission account that has resulted in an overpayment to you of $__________. This occurred because...

Please accept our apologies for this oversight. We'd entertain any idea that will result in the account being brought into balance.

Very Truly yours,

Your employer

Calling the employee into the office and going over with him in person the issue , how it happened, and working out a repayment plan is what you should do.