United Carry-On and Personal-Item Size Rules

Read the current United page

United's baggage rules are tied to the current booking and published sizer. Start with the official carry-on page rather than a third-party summary or a bag maker's claim. Open the policy page alongside the reservation so the dimensions are read with the actual fare and itinerary. A retailer carry-on label is not evidence of United compliance. United Carry-On Bags is the primary current reference for the rule described here. Deep Arrival checked the official sources for United Carry-On and Personal-Item Size Rules on September 2, 2026; recheck them after any fare or itinerary change.

Measure the whole exterior

A cabin bag must fit the sizer with wheels, handles, and exterior pockets included. Measure after packing because expansion can change the bag's actual footprint. Measure from the widest loaded point, including wheel housings, handles, and external pockets. Test after packing, because a jacket or laptop can change the footprint. The published details in United Checked Bags should be rechecked before departure.

Give the personal item a clear role

The personal item must fit under the seat. Use it for the items you need in flight and for items that should stay with you if an overhead bag is checked. Place items needed during a delay or a gate check in the underseat bag. This should include medication, identification, payment cards, chargers, and a small battery pouch. United Contract of Carriage supplies the authoritative limit or procedure used in this section.

Check Basic Economy carefully

United's Basic Economy restrictions can differ by route and ticket. Confirm the exact fare conditions in the booking before choosing a second cabin bag. Read the fare rules before selecting seats or adding a bag. Basic Economy conditions can depend on the exact route and any applicable exception shown in the booking. Use FAA Carry-On Baggage Tips to confirm the current version of this guidance.

Expect aircraft differences

A compliant bag can still face a gate check when smaller aircraft or a full flight limit overhead space. Keep the personal item genuinely usable on its own. Check the aircraft and connection time in the reservation, then plan for an equipment substitution. Smaller overhead bins can change how a compliant bag is handled at boarding.

Follow the operating carrier

A United flight number can be operated by another airline. The carrier physically operating the segment can have different size or allowance rules. For every codeshare, identify the airline marked operated by and open its baggage page. The marketing code alone does not confirm the cabin-bag treatment.

Prepare for a gate check

FAA guidance keeps power banks and spare batteries in the cabin. Remove them, along with documents, medication, and valuables, before handing over a bag. If a bag is taken at the gate, remove power banks and spare batteries before it enters the hold. Keep the tag or receipt until the bag is returned.

Use the itinerary as the final source

The airline's bag calculator and reservation details can show fare and route qualifiers that a general policy page cannot capture. Run the bag calculator again after a voluntary change, rebooking, or carrier substitution. The ticketed itinerary is the final practical check before the airport.