Most US airlines now treat a boxed bike as a normal checked bag. The catches are weight, size, and one carrier that will not take a case this big. Here is the short version for the Thule RoundTrip Transition you are renting.
Outside
54 × 37 × 15.5 in
Linear inches
106.5
Empty weight
39 lb
Packed
55 to 70 lb
Two numbers matter at the counter. The box is 106.5 linear inches, which clears the 115-inch limit on the big carriers but is far over the 62 inches of a normal bag, so it only flies where the airline waives oversize for bikes. And with a bike inside it weighs more than 50 lb, so on most airlines expect a $100 overweight fee on top of the bag fee. Pack light and weigh it at home.
Checked against each airline's own policy page in September 2026. Fees change; the link in each row is the source of truth on the day you fly.
| Airline | What you pay | Weight | Size |
|---|---|---|---|
United Counts as a bag | Standard checked-bag fee (about $45 to $50 for a first bag). No bike fee, no oversize fee. Pedals off, handlebars sideways. No e-bikes. | 50 lb before overweight fees: $100 at 51 to 70 lb, $200 at 71 to 100 lb. | Up to 115 linear inches. This box is 106.5, so it clears. |
Delta Counts as a bag | Standard checked-bag fee (about $35 to $45 for a first bag). No oversize fee for bikes. A hard-shell bike case means no limited-release form to sign. | 50 lb, then the excess-weight fee: $100 at 51 to 70 lb, $200 at 71 to 100 lb. | Refused over 115 linear inches. This box is 106.5, so it clears. |
American Counts as a bag | Standard checked-bag fee (about $40 to $50 for a first bag). Oversize fee removed for bikes. Handlebars sideways, pedals off or wrapped. | 50 lb, then the overweight fee (roughly $100 to $150 by route). Hard limit 70 lb. | Up to 126 linear inches. This box is 106.5, so it clears. |
Southwest Counts as a bag | Standard checked-bag fee ($35 now, $45 for tickets bought on or after April 9, 2026). Oversize fee waived. Non-motorized single-seat bikes only. Pedals and handlebars must be removed and padded. | 50 lb, then $100 at 51 to 70 lb and $200 at 71 to 100 lb. | Refused over 115 linear inches or 100 lb. This box is 106.5, so it clears. |
Alaska Counts as a bag | Standard checked-bag fee (about $35 for a first bag). No bike fee. Applies to Horizon and SkyWest flights on an Alaska ticket too. | Overweight waived up to 70 lb, then $100. The friendliest weight rule of the bunch. | Up to 115 linear inches. This box is 106.5, so it clears. |
Frontier Flat bike fee | $100 bike fee each way, on every fare. It replaces the bag fee, and there are no overweight or oversize charges on top. Frontier asks for an extra 30 minutes at check-in for bikes. | Refused over 99.9 lb. No weight fee below that. | Refused over 109 linear inches. This box is 106.5, so it clears, but only just. Strap nothing to the outside. |
JetBlue Box too big | $100 bike fee on top of the bag fee, but the size rule is the real problem. Fly a different carrier, or ship the bike ahead. | 50 lb. | Hard limit of 80 linear inches, even with the bike fee paid. This box is 106.5, so JetBlue will not take it. |
Weigh it at home
The box alone is 39 lb, so a packed bike lands around 55 to 70 lb. That is over the 50 lb line on most airlines, which means an overweight fee, not a refusal. Weigh yourself holding the box on a bathroom scale and subtract.
Pedals off, bars sideways
Every airline asks for it. Bring a 15 mm pedal wrench or an 8 mm hex key, turn or drop the handlebars, and shift into the smallest cog so the rear derailleur sits tucked in. Pad it.
Nothing pressurized, nothing lithium
Leave CO2 cartridges at home; TSA will pull them. E-bike batteries cannot fly in the box or in the cabin. A mini pump and a multi-tool are fine in the box.
Book the bike in advance where you can
Prepaying the bag fee online is usually cheaper than at the counter, and some carriers want to know a bike is coming. Take a screenshot of the airline policy page; agents sometimes quote fees from a previous year.
Give yourself 30 to 45 extra minutes
Oversize items go to a separate bag drop, and the box needs to be screened. On arrival, look for the oversize baggage door, not the carousel.
Photograph the packed bike
Two photos of the bike inside the open box and one of the closed box before you hand it over. If anything is damaged in transit, that is your claim.
Pick your dates, and your host will text you a pickup time.