Abstract: An automatic coin-operated stamping mailbox having a coin collector which activates a first switch. A letter to be mailed is inserted into a slot which activates a second switch in series with the first thereby operating a motor driving a set of rollers which mark the letter. A third switch following the rollers keeps the motor going until the letter clears the rollers and drops into a letter cabinet. A gear system coupled with the coin controller deactivates the first switch; since the second and third switches are normally open, the motor shuts down as soon as the letter clears.