Originally Posted by darryl gesner
This is the actual regulation section covering this:
3.1.3 Use for Mail
Except under 3.2.11, Newspaper Receptacle, the receptacles described in 3.1.1 may be used only for matter bearing postage. Other than as permitted by 3.2.10, Delivery of Unstamped Newspapers, or 3.2.11, no part of a mail receptacle may be used to deliver any matter not bearing postage, including items or matter placed upon, supported by, attached to, hung from, or inserted into a mail receptacle. Any mailable matter not bearing postage and found as described above is subject to the same postage as would be paid if it were carried by mail.
I think that makes it pretty clear! You can't legally put your flyer in or on a mail box or it's post. You can put it in a mail slot in a door though. Where I am, the postal carrier will collect any flyers they find and you will be charged the postage that would have been due if you mailed them.
If what I read is the exact wording of the regulation, I believe there is a loophole. It says "no part of a mail receptacle may be used to deliver any matter not bearing postage". It does not state that it must be correct postage. You could put a one cent stamp on your flyer and put it on the mailbox, or for a matter of fact, inside it legally. Also, It does not state who must deliver it. So you would be able to do it yourself.