Frontier Bag Sizes: A 35 lb Cap on the Free Personal Item and 40 lb Checked

Photo by Phil Mosley on Unsplash

Frontier is the only airline in this group that puts a weight limit on the personal item: 18 x 14 x 8 inches and up to 35 lb. The carry-on is 24 x 16 x 10 inches, also 35 lb — and it is not included in the fare. The checked bag limit is 62 linear inches and up to 40 lb, ten pounds below the 50 lb that every other airline here allows.

The numbers, exactly as Frontier Airlines prints them

Where these numbers come from: Frontier Airlines carry-on page, Frontier Airlines checked bag page. Read and recorded on 2026-08-31. Every figure on this page is copied from those pages — nothing here is estimated. Airlines change baggage rules without notice, so check the official page before you fly.

The free bag is the small one, and it gets weighed

The order of the Frontier page tells you the business model. The personal item comes first — "One included with all fares" — and the carry-on comes second with "Add when you book for the best price!" On Frontier, the free bag is the small one, and the cabin bag is a product you buy.

Both are capped at 35 lb, which is the detail that separates Frontier from every other airline here. Nobody else publishes a personal item weight limit at all. Frontier also says the size "will be checked during boarding" and that oversize items "are subject to an additional charge," so this is an enforced limit rather than a stated one.

The free personal item is, however, physically large: 18 x 14 x 8 inches, the same footprint American allows, and considerably bigger than United's 17 x 10 x 9 or Korean Air's 40 x 30 x 15 cm. At roughly 33 litres it will take three or four days of clothes if you pack it like a carry-on rather than like a handbag. For a short trip on Frontier, the correct move is usually to buy nothing and pack the personal item properly.

Frontier also sells the thing that makes the carry-on usable. Its page offers "Board First — Board with Group 1 and guarantee overhead bin space for your bag," and says to add it when you buy the carry-on. That is worth reading as a warning rather than an upsell: on a full Frontier aircraft, buying the carry-on does not by itself guarantee a bin, and a gate-checked bag on a cheap fare undoes most of the reason you paid for it.

The checked limit is where Frontier differs from the whole group and where the surprise fee usually comes from: up to 40 lb, against 50 lb at American, United, Delta, Southwest, JetBlue and Air Canada, and 23 kg at Korean Air. A bag packed to a habitual 48 or 49 pounds is comfortably legal on seven of these eight airlines and overweight on Frontier. The linear size limit, 62 inches, is the same as everyone else's.

Measuring your own bag against these numbers

The bag most retailers label "the standard carry-on" is 22 x 14 x 9 inches. Converted exactly, that is 55.88 x 35.56 x 22.86 cm, and the three sides add to 114.3 cm. Held against Frontier Airlines's published limits, here is where it stands.

It fits. Every side of the standard bag is inside Frontier Airlines's published maximum of 61 × 40.6 × 25.4 cm. That gives you room to spare in the directions where it matters, but the margin exists only for an unpacked bag: soft sides bulge, and hard shells bow at the lid when overfilled.

The reverse question matters just as much if you already own luggage. A bag bought to fit Southwest Airlines, Air Canada, JetBlue, American Airlines, United Airlines, Delta Air Lines, Korean Air also clears Frontier Airlines.

Whichever airline you are flying, measure the same way the airline does: bag packed, tape across the widest bulge rather than the frame, wheels and handle included, expansion zip closed. Every airline on this page that says anything about wheels says they count.

What Frontier Airlines does not publish

These were checked against Frontier Airlines's own baggage pages on 2026-08-31. The following are simply not stated there, so treat any number you find elsewhere for them as somebody's inference rather than a rule:

• A carry-on weight limit
• The carry-on size in centimetres
• A combined length + width + height cap
• Personal item dimensions in centimetres
• The checked bag size in centimetres
• The checked bag weight in kilograms

Frontier publishes no centimetre figures at all. Every number on their bag page is in inches and pounds.

How Frontier Airlines compares with the other seven

Frontier shares the largest cabin box with Southwest, but charges for it, and has the lowest checked weight limit of the eight. Frontier Airlines ranks second of the eight by published cabin volume at 62.9 litres, between Southwest Airlines's 62.9 at the top and Korean Air's 44.0 at the bottom. Volume is the published box multiplied out, which is the fairest way to compare boxes of different shapes.

† converted from the figure the airline does publish. Southwest and Frontier publish inches only; Korean Air publishes centimetres only. Everything without a dagger is printed on the airline's own page in that unit.

The full eight-airline table, including checked bag limits, is on the comparison page. Alaska Airlines is deliberately absent from it: its baggage pages would not open to us, and we would rather leave a gap than print a figure we could not read on an official page.

What to buy, and what not to buy, for Frontier

For trips of up to about four days, buy nothing. Pack the free 18 x 14 x 8 personal item properly and keep it under 35 lb. That is the whole Frontier strategy, and it is why the personal item dimensions are the most important numbers on their page.

If you must check, weigh at 40 lb, not 50. It is the single most common way to pay Frontier more than you planned, and a kitchen scale settles it before you leave.

The other seven airlines

• Southwest Airlines carry-on and checked bag sizes
• Air Canada carry-on and checked bag sizes
• JetBlue carry-on and checked bag sizes
• American Airlines carry-on and checked bag sizes
• United Airlines carry-on and checked bag sizes
• Delta Air Lines carry-on and checked bag sizes
• Korean Air carry-on and checked bag sizes

Related pages on TripPack

• All eight airlines in one table — carry-on, personal item and checked limits side by side.
• Carry-on packing list — what to actually put in the bag once you know it fits.
• How to measure a carry-on bag — where to hold the tape.
• Baggage weight limits explained.