Allegiant Air allowance at a glance
| Bag | Maximum size | Maximum weight | Notes |
|---|---|---|---|
| Carry-on | 22x16x10 in55x40x25 cm | No stated limit | A carry-on is not free on most Allegiant fares. It is a paid add-on published at $10 to $75 depending on route and when you buy it, and is included only with bundles that cover it. No carry-on weight limit is published. |
| Personal item | 18x14x8 in45x35x20 cm | No stated limit | One personal item is free on every fare and must fit under the seat. |
| Checked bag | 80 in203 cm | 50 lb22 kg |
This page goes deeper on one part of the policy. The full record is at Allegiant Air Baggage Rules.
Allegiant does not give most travelers a free carry-on bag. Understanding Allegiant carry-on size only matters once you have paid for the privilege. The overhead bin slot is an add-on priced between $10 and $75, depending on the route, the fare and when you buy it, according to Allegiant’s own baggage page.
The box itself is 22 by 16 by 10 inches, or 55 by 40 by 25 cm. Allegiant publishes no weight cap for it. That is a little more forgiving than the tight 22 by 14 by 9 box some low cost carriers use, which matters when you compare bags below.
Everyone gets one free personal item, and it has to slide fully under the seat in front of you. If the free item is all you plan to bring, you can skip the carry-on fee entirely. Read our guide to personal item versus carry-on rules first, or check the full rundown on our Allegiant baggage rules page for checked bags and fees.
How strictly Allegiant checks the sizer
Traveler reviews describe enforcement as inconsistent rather than absent. One passenger flew Allegiant four times with the same backpack and was waved through every time. On a fifth flight the same bag was called overstuffed and the passenger paid $75 at the gate.
The gate agent reportedly said the earlier trips were luck, not a rule change. That kind of unevenness shows up often on carriers that sell the overhead bin as an add-on. A gate agent running behind schedule has less patience for a bag that looks close to the line.
Our gate check and sizer explainer covers what happens once a bag gets pulled aside. The practical lesson for Allegiant carry-on size is simple. Pay for the bag online if you plan to use the bin, and keep it looking obviously compliant rather than betting on a light touch at the gate.
Why Allegiant has no flat fee table
Allegiant prices carry-on and checked bags dynamically. The price moves by route, by whether you bought a bundle and by when you pay. Gate pricing runs highest of the three.
That is different from a carrier that posts one fixed number for a first checked bag. One traveler in a published review described paying $30 online for a bag. The online option later went grey on the app, and the airport charged $75 per bag instead.
Lock the carry-on fee in during booking rather than leaving it for the gate. Some Allegiant fare bundles fold the fee into the ticket price. If your fare does not name a carry-on in its bundle, assume you are paying the add-on separately and check the price at booking.
What happens when a bag does not fit
A bag that fails the gate check gets checked at the counter’s discretion. The traveler pays whatever that check costs at that point in the booking window, usually the most expensive tier. Allegiant’s checked allowance runs to 80 linear inches, or 203 cm, and 50 lb, or 22 kg, before the overweight bands start.
Overweight runs $50 for 51 to 70 lb. It runs $75 for 71 to 100 lb, and nothing over 100 lb is accepted. Oversize bags past 80 linear inches add $75 on top.
Neither figure applies to a normal bag that simply gets gate checked for lack of bin space. That check is usually waived. A bag that is truly over the box’s dimensions is the one that risks the oversize charge instead.
Bags that fit the box
The 22 by 16 by 10 inch box gives a little more room than the strictest budget carriers use. A standard 20 inch hardside clears it with room to spare. A popular 21 inch softside spinner runs into trouble the moment its handle gets measured in.
| Bag | Maker’s overall size | Fits the 22x16x10 box |
|---|---|---|
| Samsonite Omni PC 20 inch hardside spinner | 22 x 15 x 9.8 in, per its retail spec sheet | Yes, inside all three dimensions |
| Travelpro Maxlite 5 21 inch softside carry-on spinner | 23 x 14.5 x 9 in overall, unexpanded, per Travelpro | No. The 23 inch height, wheels and handle included, exceeds the 22 inch limit even unexpanded |
| Narwey personal item bag 18x14x8 | 18 x 14 x 8 in, built to that exact box | Fits the free personal item slot, not the paid carry-on box |
The Maxlite 5 result is worth remembering for Allegiant carry-on size shoppers. It is one of the most reviewed carry-ons sold. Many buyers assume any 21 inch spinner clears any airline’s box.
Travelpro’s own listing notes a fully expanded bag may not clear a strict sizer. On Allegiant it does not clear even unexpanded, once the handle is measured.
Check your own bag rather than trust a spec sheet alone. Our size checker tool compares your bag’s exact measurements against the box in seconds.
How Allegiant compares
Allegiant sits in the same paid carry-on category as Frontier and Avelo. The free item is a personal item only, and the overhead bin bag is an extra you buy. Allegiant carry-on size at 22 by 16 by 10 inches is a little larger than some ultra low cost peers.
That is one reason a bag that fails on a stricter carrier can still clear Allegiant. None of that changes the economics. Our guide to basic economy carry-on rules explains why the cheapest fare on a receipt rarely means the cheapest trip once bags get added.
The bottom line
Treat the Allegiant carry-on fee as part of the ticket price if you plan to use the overhead bin. Buy it online where it is cheapest. Measure your bag against the 22 by 16 by 10 inch box before you fly and lean on the free personal item whenever a trip allows it.
A gate agent who waves an oversized bag through today is not a promise for the next flight. Pack to the box, not to the reputation of a lenient gate crew.
Common questions
Does Allegiant charge for a carry-on bag on every fare?
Yes, on nearly every fare the overhead bin bag is a paid add-on separate from the free personal item, priced from about $10 to $75 depending on route and timing.
How big can my Allegiant carry-on be?
Allegiant’s box is 22 by 16 by 10 inches, or 55 by 40 by 25 cm, with no published weight limit for the carry-on itself.
What happens if my Allegiant carry-on does not fit at the gate?
It gets checked at the counter’s discretion and you pay whatever that check costs at that point in the booking process, which is usually the most expensive tier.
Does Allegiant weigh carry-on bags?
Allegiant publishes a size limit for its carry-on box but no separate weight cap for that bag.
Is it cheaper to add a carry-on online or at the airport?
Online is consistently the cheapest option, with airport and gate pricing running higher on Allegiant.
What is Allegiant's free personal item size?
The personal item is 18 by 14 by 8 inches, or 45 by 35 by 20 cm, and must fit fully under the seat.
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