"Can I mail this?" is the question we hear most at our counter, and it is always better to ask before you pack. USPS sorts every item into three buckets: prohibited (never allowed), restricted (allowed only if you follow specific rules), and mailable (good to go). Put an item in the wrong bucket and your package can be returned, destroyed, or land you in legal trouble.

This guide gives you the full prohibited and restricted items list in plain English, answers the questions people actually ask, and shows you what to do instead when USPS says no. One note before we start: the official rules live in USPS Publication 52, and they change from time to time. Treat that publication as the final authority and this guide as the plain-English version.

Prohibited vs Restricted vs Hazardous: The Short Answer

Prohibited means USPS will never accept it from a regular shipper, no matter how you pack it. Fireworks, gasoline, and handguns mailed by unlicensed individuals fall here.

Restricted means you can mail it, but only if you follow specific rules about packaging, labeling, quantity, and which service you use. Alcohol, lithium batteries, and aerosols fall here, and the rules are where most people trip up.

Hazardous is the word that gets packages seized. If your item carries a hazmat diamond, a flammable warning, or a skull and crossbones, stop and check the rules before it goes anywhere near a mailbox.

Never Mailable: The USPS Prohibited Items List

These are banned from the mail outright. No exceptions for regular shippers:

  • Explosives and fireworks. Firecrackers, sparklers, blasting caps, and anything designed to explode or burn rapidly.
  • Ammunition. Small arms ammunition, primers, blank cartridges, and propellant powder are prohibited.
  • Flammable liquids. Gasoline, lighter fluid, turpentine, oil-based paints, and similar liquids.
  • Flammable gases. Propane tanks, butane canisters, and lighters. Yes, that includes the disposable lighter in your pocket. We get asked about this one constantly.
  • Poisons and toxic substances. Pesticides, mercury (including old thermometers that contain it), and other materials classified as toxic.
  • Corrosives. Strong acids and other materials that can eat through packaging or injure handlers.
  • Marijuana. Prohibited regardless of your state's laws. Mail is federal, so state legalization does not apply.
  • Strike-anywhere matches. Completely banned. Safety matches may be allowed by ground service, but the strike-anywhere kind cannot go at all.
  • Air bags. Automotive air bags are classified as explosive devices and cannot be mailed.
  • Counterfeit goods, lottery materials, and obscene materials. Nonmailable under federal law.

If it burns, explodes, or is marked with a skull and crossbones, assume it is prohibited and look for a hazmat carrier or a local disposal option instead.

Restricted Items: Allowed Only Under Certain Rules

This is the category that causes the most confusion, because the answer is usually "it depends." Here are the items people ask about most.

Alcohol

Individuals generally cannot mail beer, wine, or spirits through USPS at all. This is one of the most common surprises at the counter. Even licensed businesses face strict rules. If you need to ship alcohol, UPS and FedEx accept it from licensed shippers under their own compliance programs, or you can order from a retailer licensed to ship to the recipient's state.

Firearms and Ammunition

Handguns cannot be mailed by unlicensed individuals, period. Rifles and shotguns have their own set of rules and generally move through licensed dealers. The short version: do not put a firearm in the mail unless a licensed dealer is handling the shipment.

Lithium Batteries

This one depends entirely on the type. Batteries installed in a device, like your phone or laptop, are generally fine to mail. Standalone and spare lithium batteries face quantity limits, packaging rules, and service restrictions. Damaged, swollen, or recalled batteries should never be mailed normally. If you are shipping a device with a battery inside, proper cushioning matters a lot, so read our guide on how to ship a laptop safely or let our packing services handle it.

Aerosols and Nail Polish

Some non-flammable aerosols can travel by ground service in limited quantities with proper marking, but they cannot fly. Most spray paints and many hairsprays are flammable, which puts them in the no-fly category. Nail polish and hand sanitizer fall in the same trap: both are flammable, so they face strict ground-only rules. These are the items people toss in a box without thinking, and they are among the most commonly intercepted.

Perfume and Cologne

Most perfumes are alcohol-based and flammable, which means they cannot travel by air. Limited ground options exist under strict packaging rules, but in practice it is simpler to use UPS or FedEx ground or buy the fragrance locally at the destination.

Prescription Medications

Only authorized parties, such as registered practitioners and dispensers, can mail prescription drugs, and patients may do so only under specific conditions. There are labeling and packaging requirements. When in doubt, ask your pharmacy.

Cremated Remains

These are actually mailable, but only through Priority Mail Express with special labeling and packaging. It is a sensitive shipment with a specific process, so ask the counter staff to walk you through it step by step.

Perishables, Plants, and Live Animals

Some perishable foods are allowed with proper packaging and fast service, but many plants and food items face state agricultural restrictions, so check both USPS rules and your destination state's rules. As for live animals, USPS basically only accepts day-old poultry shipped from hatcheries under strict packaging conditions. No cats, no dogs, no pets of any kind.

International Mail Has Extra Rules

Everything above applies to international mail, plus more. Every country sets its own import prohibitions, and USPS enforces them. Common international bans include perfume and cologne, nail polish, certain foods and seeds, used electronics in some countries, and anything the destination country lists as prohibited. A package that is perfectly legal domestically can be seized by customs abroad, so check the USPS country conditions for your destination before you ship.

What Happens If You Mail a Prohibited Item?

The consequences range from annoying to serious, and we have seen all of them:

  • Your package gets returned or destroyed. USPS can intercept prohibited items during processing, and you may never see the item again.
  • You lose the shipping cost. Postage on a seized package is not refunded.
  • Fines and legal trouble. Knowingly mailing hazardous materials can bring civil penalties and, in serious cases, criminal charges.

It is never worth the risk. If you are unsure about an item, ask before you ship. For items that are fully mailable, shipping protection is still worth considering, because the rules being on your side does not make a package indestructible.

Safe Alternatives for Common Problem Items

  • Instead of mailing alcohol, use a licensed alcohol shipper through UPS or FedEx, or order from a retailer that ships to the recipient's state. Compare your carrier options on our shipping page.
  • Instead of mailing perfume or nail polish by air, send them via a carrier ground service with proper labeling, or buy the product locally at the destination.
  • Instead of mailing aerosols by air, check whether they qualify for ground service under limited-quantity rules, or buy them at the destination.
  • Instead of mailing a spare lithium battery, keep it installed in the device, which faces far fewer restrictions.
  • Instead of mailing gasoline, paint, or chemicals, these need a hazmat carrier or a local purchase. There is no USPS workaround.
  • Instead of mailing a firearm yourself, go through a licensed dealer who handles the transfer legally.
  • Instead of guessing, bring the item to a pack and ship store and ask. A two-minute question beats a destroyed package.

Frequently Asked Questions

Can you ship alcohol via USPS? No. Individuals cannot mail beer, wine, or spirits through USPS, and even licensed shippers face heavy restrictions. UPS and FedEx accept alcohol from licensed businesses under their own programs.

Can you ship lithium batteries via USPS? It depends on the type. Batteries installed in devices, like a phone or laptop, are generally allowed. Standalone lithium batteries face strict limits on quantity, packaging, and service type. Damaged or recalled batteries should never be mailed.

Can you ship perfume via USPS? Generally no, because most perfumes are flammable and cannot travel by air. Limited ground options exist under strict rules, but it is usually easier to use UPS or FedEx ground or buy the fragrance locally.

Can you ship nail polish via USPS? Nail polish is flammable, so it faces the same restrictions as other flammable cosmetics. It cannot fly, and ground shipment requires proper packaging and marking under limited-quantity rules.

Can you ship marijuana through USPS? No. Marijuana is prohibited in the mail regardless of state law, because the postal system is federal. This surprises people regularly, but there is no legal workaround through USPS.

What happens if you mail a prohibited item? USPS can intercept the package during processing and return or destroy it, and your postage is not refunded. Knowingly mailing hazardous materials can also bring civil penalties or criminal charges in serious cases.

The Bottom Line

Most everyday items ship through USPS without any trouble. The problems start with anything flammable, explosive, toxic, or federally restricted, and with a handful of everyday products like perfume, nail polish, aerosols, and spare batteries that people do not realize are regulated. When in doubt, check USPS Publication 52 or ask someone who handles these questions all day.

Have an item you are unsure about? Bring it to Print N Ship 4u in Katy, TX and we will tell you exactly what can go, which service to use, and how to pack it to meet the rules. If USPS cannot take it, we will check UPS, FedEx, and DHL for you. Call us at (281) 375-9714 and ship with confidence.

Want to plan the rest of your shipment too? See how much it costs to ship a package once you know your item is good to go.