Michigan residents count on the United States Postal Service for everyday mail and delivery needs. Checking the mailbox for letters, bills, and important documents is part of daily life. But now, USPS has issued an urgent message urging Michigan residents to inspect their mailboxes right away.

USPS Teams Up With Postal Inspectors to Keep Communities Safe

In collaboration with the U.S. Postal Inspection Service, USPS works to protect postal workers, secure the mail stream, and uphold the laws that safeguard our national mail system. Now, they’re calling on Michigan residents to play a part in boosting the safety and reliability of mail delivery in their own neighborhoods.

Mailbox Improvement Week: Time for a Check-Up

Every year during the third week of May, USPS holds Mailbox Improvement Week, encouraging customers with box-on-post delivery to inspect and upgrade their mailboxes. To support this effort, USPS urges Michigan residents to take a few moments to ensure their mailboxes are in top shape for safe and efficient deliveries. A basic inspection may involve:

• Replacing loose hinges on the mailbox door
• Repainting to cover rust or peeling paint
• Remounting the mailbox if the post is unstable
• Clearing a direct path for easy access
• Trimming vegetation that hides the house number or mailbox
• Adding or replacing visible house numbers

Residents may also want to upgrade to a larger capacity mailbox for smoother, more efficient deliveries.

9 Items You Absolutely Cannot Send in the Mail in Michigan

You can find the full list of U.S. Postal restrictions and more details by checking official USPS guidelines online.

Mercury

“Liquid mercury on its own or contained in various items is prohibited in the mail. Liquid mercury is a hazardous substance that produces toxic vapors if exposed to air and causes mercury poisoning if the vapors become inhaled. Older styled thermometers, blood pressure gauges, and barometers — which often contain liquid mercury– may become damaged or broken during the shipping process.”

Marijuana

This probably goes without saying—marijuana, whether medical or recreational, is not mailable. Hemp and CBD are allowed but come with restrictions.

Gasoline

Gasoline and other explosive substances are completely banned from the mail.

Air Bags

Why someone would want to mail an airbag is unclear—but they’re not allowed either.

Lithium Batteries

“Lithium batteries power numerous electronics from cell phones, laptops, and tablets to wireless headphones, toys, and portable tools. What is not generally known is that these batteries are considered hazardous materials and remain highly regulated in transportation.”

Fireworks

Mailing fireworks is completely illegal.

“Illegal shipments of fireworks pose a significant hazard while in air transportation and endanger the lives of Postal employees and the traveling public.”

Firearms

Sending firearms through USPS comes with strict rules.

“Only licensed manufacturers and dealers may mail or receive handguns. Even though unloaded rifles and shotguns are mailable, mailers must comply with applicable regulations.”

Ammunition

Many people don’t realize that ammunition is classified as an explosive, which is why USPS won’t accept it.

“Small arms ammunition is categorized as explosive materials by the U.S. Department of Transportation.”

Pets

Thinking of mailing your pet? Don’t. Live animals are considered “un-mailable” by USPS.

This article has been carefully fact-checked by our editorial team to ensure accuracy and eliminate any misleading information. We are committed to maintaining the highest standards of integrity in our content.