Can you put flyers in mailboxes?

It is illegal to put anything in a U.S. Mail box unless proper postage has been paid, according to the United States Code. This includes such items as circulars and sale bills, which would include flyers.

While often this law is not strictly enforced, mainly because doing so costs time and resources that are better spent elsewhere, the law still strictly forbids the practice. According to the United States Postal Service, the only legal way to pass out flyers, or any other material, through the mail is to purchase postage from the post office and mail it the proper way.