Frontier Airlines Checked Baggage

Frontier caps a checked bag at 40 pounds. That is ten pounds lighter than the 50 pound ceiling most US carriers use. It drives the whole Frontier checked baggage size story.

Pack heavy and the case itself eats the allowance, not your clothes.

The Frontier Airlines record lists the headline numbers Frontier verifies today. 62 linear inches (158 cm) and 40 pounds (18.1 kg) per checked bag. Both figures come from Frontier’s Optional Services page.

This page goes deeper on the Frontier checked baggage size details that trip people up.

What your fare actually includes

Frontier’s base fare, the one shown first in search results, includes a seat and a personal item. Nothing else.

A checked bag costs extra on every fare unless it comes bundled in. Frontier’s Business Bundle is the one fare class that includes checked bags. It covers two bags, up to 50 pounds each, a higher cap than the standard Frontier checked baggage size limit.

Frontier prices a standalone checked bag with a Bag Price Checker, not one flat number. The fee moves by route, travel date and how far ahead you buy it. Buying online ahead of time is consistently cheaper than adding a bag at the counter or the gate.

The 40 pound limit in practice

Every checked bag on Frontier tops out at 40 pounds and 62 linear inches. That is length plus width plus height added together.

Go over on weight and Frontier charges a fee. It does not turn you away, at least up to a point.

A bag between 41 and 50 pounds costs 75 dollars extra, per bag, per direction. Between 51 and 99.99 pounds the charge jumps to 100 dollars.

That price rises to 129 dollars for bags booked on or after April 4, 2026. A bag at 100 pounds or heavier is not accepted at all.

Oversize works the same way in reverse. A bag between 63 and 110 linear inches costs 75 dollars extra, per bag, per direction.

See this site’s checked baggage weight limit guide for how that compares to other carriers. Anything over 110 linear inches is refused outright.

Community reports describe Frontier counter staff weighing every bag rather than eyeballing it. The airline collects real revenue on every pound over 40. A scale at home is not optional if you are packing close to the line.

Do not count on shifting weight between two checked bags at the counter. Travelers report Frontier agents weighing each bag on its own, so a 45 pound bag next to a 30 pound bag still triggers the overweight fee on the heavier one. Pack toward an even split before you leave the house rather than hoping to rebalance at the airport.

What cannot go in the hold

Frontier’s own baggage page lists items it wants kept out of a checked bag. Medication, cash, electronics, car keys, important documents and other valuables are better carried in the cabin. Standard hazmat rules also apply: aerosols, weapons, corrosives, explosives, radioactive materials, oxidizers, flammables and toxins are all banned.

Lithium batteries belong in the cabin, not the hold. That covers spare battery packs and smart bags with a built in charger. A bag with a non removable lithium battery generally cannot be checked at all.

Antlers and bicycles fly as special checked items on Frontier. Each has its own fee, outside the standard weight bands. Firearms and sporting equipment like skis or golf clubs have to be declared at the counter, not sent through as an ordinary bag.

Connecting tickets and codeshares

Frontier is a point to point carrier. It does not run the kind of codeshare network that regularly puts its bags under another airline’s rules.

That is a real advantage for anyone comparing carriers, since a codeshare partner’s staff sometimes applies its own weight cap rather than the ticketing airline’s, and a traveler finds out only at the counter.

Book Frontier on one reservation, even across a connection, and Frontier’s own limits apply straight through: 40 pounds, 62 linear inches. Book two separate tickets on two different airlines instead, and each carrier’s own checked baggage size rules apply to its own leg. Nothing guarantees your bag transfers between them.

See this site’s guide to checked bags on connecting flights for how that plays out at the counter.

Packing to the 40 pound line

An empty case matters more on Frontier than on most US carriers. Ten fewer pounds of allowance leaves less room for a heavy shell before you pack a single shirt.

Run the baggage cost tool before you book. A checked bag plus a likely overweight fee can rival a Business Bundle fare on a short route.

Whichever case you check, a digital luggage scale settles the question at home. A counter reading you cannot dispute costs 75 dollars or more.

How Frontier compares

Allegiant runs a similar unbundled model. See the Allegiant baggage fees page for how its checked bag pricing stacks up.

For the carry-on and personal item side of Frontier’s bundle, see the Frontier baggage fees page. The Frontier carry-on size page covers the cabin bag rules.

The bottom line

Frontier checked baggage size comes down to two firm numbers: 40 pounds and 62 linear inches. Buy the checked bag online ahead of time. Weigh it at home and pick a light case so the allowance goes to your clothes, not the shell.

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