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Airline Carry-on Size Rules

Compare major airline carry-on limits in one place. This page is designed to reduce check-in surprises and help you pick the right suitcase.

Carry-on Size Check in Real Travel Context

Traveler comparing carry-on luggage with a size checker frame

This scene reflects how carry-on limits are enforced in practice: your bag must match policy dimensions and fit size-check constraints.

If your suitcase is near the limit, prioritize a small size buffer to reduce gate-check risk on stricter routes.

Major Airline Carry-on Comparison

Swipe horizontally to view full table

AirlineCarry-on (in)Carry-on (cm)Personal ItemSource
Delta Air Lines22 x 14 x 956 x 35 x 23Must fit under seatofficial2026-03-20
American Airlines22 x 14 x 956 x 36 x 2318 x 14 x 8official2026-03-20
Southwest Airlines24 x 16 x 1061 x 41 x 25One personal item free, under-seat fit requiredofficial2026-03-20
United Airlines22 x 14 x 956 x 35 x 2318 x 14 x 8secondary2026-03-20
JetBlue22 x 14 x 955.9 x 35.6 x 22.9One personal item under-seat fitsecondary2026-03-20
Frontier Airlines24 x 16 x 1061 x 41 x 2518 x 14 x 8official2026-03-20
Allegiant Air22 x 16 x 1055.9 x 40.6 x 25.418 x 14 x 8official2026-03-20

Quick Facts

This section summarizes how to interpret airline carry-on data correctly.

Data unit priority
Use single-side dimensions first (in/cm)
Most common US baseline
22 x 14 x 9 in, but not universal
Personal item rule
Must fit under seat; some airlines publish exact dimensions
Main decision sequence
Check airline > check fare class > check aircraft constraints
When to re-check policy
24-48 hours before departure
How Airlines Calculate Luggage Size

Airline baggage limits in inches are based on the outer box dimensions of your bag, not volume.

  • Carry-on rule (most common): single-side limits such as 22 x 14 x 9 in (L x W x H).
  • What must be included: wheels, handles, feet, and any rigid external parts.
  • What is not used as the main rule: liters/cubic volume is usually not the acceptance criterion.
  • Sizer logic at airport: if the bag does not fit the frame, it can be denied or gate-checked.

Airline Detail Guides

Delta carry-on sizeAmerican carry-on sizeSouthwest carry-on sizeUnited carry-on sizeFrontier carry-on sizeAllegiant carry-on sizeJetBlue carry-on size

How to Use This Guide Before You Fly

  • Start with the table for a fast baseline, then open your airline detail page.
  • Check whether your ticket is basic/economy-light, since baggage allowance may change.
  • Re-check the policy 24-48 hours before departure for last-minute updates.
Data Sources