Canada Post is paid to distribute flyers and other unaddressed material.
The letter reminds residents that flyers, catalogues, product samples and community notices can "save you money and keep you connected with your local community."
Anick Losier, a spokeswoman for Canada Post, said her organization wants to be sure that citizens are not missing out on important, but unaddressed, mail.
"[The letter is] to remind people what unaddressed ad mail is," said Losier.
"It's not just flyers and coupons, it's also fundraising incentives, it's also catalogs, as well as municipal notices."
Losier said Canada Post sent out the letters to help the organizations and people who pay Canada Post to distribute flyers and notices reach more homes.
In St. John's, however, homeowners Evelyn Osborne and Peter Duchemin said the Canada Post letter will not convince them to remove the "no flyers" sign on their mailbox.
"No, it [the letter] will persuade me to absolutely keep it up," said Osborne.
Duchemin, who had been doing some painting around their property, painted an exclamation mark on the "no flyers" sign, just to make their point to Canada Post more emphatic.
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