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Last updated: April 2026
This page covers Frontier's full baggage policy — personal item limits, carry-on bag rules, fees, weight limits, and enforcement. Frontier includes one free personal item on every fare, but the carry-on bag is a paid add-on. Frontier enforces bag limits more consistently than legacy U.S. carriers, so getting the size right matters. Use this page to understand the rules, then check the size-specific fit guides below to see if your bag works.
| Bag Type | Size Limit | Weight | Cost |
|---|---|---|---|
| Personal Item | 18 × 14 × 8 in (45 × 35 × 20 cm) |
No limit | Free (all fares) |
| Carry-On Bag | 24 × 16 × 10 in (61 × 41 × 25 cm) |
35 lbs (16 kg) | Paid add-on |
| Checked Bag | 62 linear inches max | 40 lbs (18 kg) | Paid add-on |
Prices vary by route, season, and when you purchase. Buying online during booking is always cheaper than at the airport. Bundle fares may include carry-on and checked bags.
Every Frontier fare includes one free personal item that must fit under the seat in front of you. The size limit is 18 × 14 × 8 in (45 × 35 × 20 cm).
This is more generous than ultra-low-cost European carriers like Ryanair (40 × 30 × 20 cm) but smaller than the overhead bin allowance on legacy U.S. airlines. In practice, most standard backpacks, laptop bags, and purses fit within this limit. The 8-inch (20 cm) depth is usually the dimension that catches overpacked bags.
If your bag doesn't fit under the seat, it will be reclassified as a carry-on — which requires a paid add-on. Without the add-on, you'll be charged a gate fee that is significantly higher than pre-purchasing online.
To bring a larger bag into the overhead bin, you must purchase a carry-on add-on or have a fare bundle that includes it. The carry-on limit is 24 × 16 × 10 in (61 × 41 × 25 cm) with a 35 lb (16 kg) weight limit.
Frontier's carry-on dimensions are the same as Southwest's and more generous than most legacy U.S. carriers (which allow 22 × 14 × 9 in). At 10 inches of depth, the carry-on limit accommodates most standard rolling suitcases and large travel backpacks without the compression issues common on strict European airlines.
The carry-on fee varies by route and when you buy it. Adding it during initial booking is cheapest, adding it later online costs more, and paying at the gate is the most expensive option. If you know you need overhead bin space, buy the add-on during booking.
Frontier's published limits and real-world enforcement have some practical nuance. Here's what matters:
Frontier uses a sizer at the gate to check personal items, but enforcement varies by airport and staff. A soft-sided bag that's slightly over on one dimension may compress into the sizer. A hard-shell case or overpacked bag at the same dimensions won't. Being close to the limit means you're relying on inconsistency rather than compliance.
At 24 × 16 × 10 in, Frontier's carry-on limit is among the most generous in the U.S. Nearly every standard rolling carry-on and most 35–45L travel backpacks fit within these dimensions on paper. The main constraint is the 35 lb weight limit — pack heavy and you may exceed it even if the bag fits dimensionally.
A bag rated within the personal item dimensions can still fail if it's overpacked. A half-full 28L backpack compresses under the seat easily. The same bag stuffed to capacity may bulge past 8 inches in depth and get flagged at the sizer. How much you pack matters as much as what bag you use.
Bag capacity in liters doesn't directly determine whether a bag fits Frontier's rules — packed dimensions do. But here's how common backpack sizes generally map to Frontier's policy:
These are the detailed size-by-size fit pages — each one tests a specific backpack size against Frontier's exact dimension limits and shows whether it qualifies as a personal item, carry-on, or neither:
Frontier is a U.S. budget carrier with a fee structure similar to Spirit. Unlike legacy carriers (Delta, United, American) where gate agents rarely measure bags, Frontier uses a personal item sizer at the gate and enforces limits more consistently.
If your bag fails the sizer and you haven't pre-purchased a carry-on add-on, you'll be charged a gate fee — typically $60 or more. This is significantly more expensive than any pre-purchase option:
The cost difference makes pre-purchasing online significantly cheaper than risking gate enforcement. If there's any doubt about whether your bag qualifies as a personal item, buying the carry-on add-on in advance is the safer approach. Bundle fares (e.g., The WORKS) include carry-on access and are often the best value if you need overhead bin space.
The calculator accounts for Frontier's exact dimensions and shows whether your packing setup fits as a personal item, carry-on, or needs to be checked.
Open Packing Calculator →Check whether your bag's dimensions fit Frontier's limits in either unit system.
One compliant personal item for the free under-seat allowance, and two carry-on options for the paid overhead bin tier.
Frontier includes one free personal item on all fares. It must fit within 18 × 14 × 8 inches (45 × 35 × 20 cm) and go under the seat in front of you. This is typically a standard backpack, laptop bag, or purse. Anything larger is classified as a carry-on and requires a paid add-on.
Yes. Unlike legacy U.S. carriers, Frontier charges for carry-on bags unless your fare includes a bundle. The carry-on limit is 24 × 16 × 10 inches (61 × 41 × 25 cm) with a 35-pound weight limit. Purchasing the carry-on add-on online is significantly cheaper than paying at the gate.
Yes, if the backpack fits within Frontier's personal item limit of 18 × 14 × 8 inches. Many slim daypacks and laptop backpacks in the 20–25L range can fit within this limit, depending on shape and packing. Larger travel backpacks (35L+) will typically exceed the personal item dimensions and require a paid carry-on add-on.
If your bag exceeds the personal item dimensions and you haven't purchased carry-on access, Frontier will charge a gate fee to check it. Gate fees are significantly higher than pre-purchasing online — often $60 or more. Frontier uses a sizer at the gate, and staff enforce limits more consistently than legacy U.S. carriers.
Frontier's bag policy is based on their official published rules as of April 2026. Bag fees vary by route, fare type, and when you purchase. Enforcement can vary by airport and staff, but Frontier is generally more consistent than legacy U.S. carriers when it comes to personal item sizing. Bundle fares and promotions may change — always verify current pricing on Frontier's website before booking.
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