Southwest Airlines vs United Airlines

Side-by-side comparison of Southwest Airlines and United Airlines: cabin and checked baggage allowances, fees, online check-in deadlines, alliances, hubs and contacts.

Southwest AirlinesUnited Airlines
Country United StatesUnited States
Founded 19711926
Type Low-cost carrierFull-service airline
Alliance -Star Alliance
Main hubs Dallas/Fort Worth International AirportNarita International Airport, Los Angeles International Airport, O'Hare International Airport
Aircraft types 17
Cabin bag size -56 × 36 × 23 cm (22 × 14 × 9 in)
Checked bag (Economy) 1 piece · 22.7 kg (50 lb)1 piece · 23 kg (51 lb)
First checked bag fee from 45 USDfrom 45 USD
Extra bag fee from 55 USDfrom 55 USD
Online check-in opens 24 h24 h
Online check-in closes 30 min45 min
Airport check-in fee freefree
Customer service phone +1 214 792 40 00-

Key differences

  • United Airlines includes more checked baggage in the basic Economy fare: 1 piece · 23 kg (51 lb) vs 1 piece · 22.7 kg (50 lb) at Southwest Airlines.
  • Southwest Airlines lets you check in online closer to departure (30 min vs 45 min).
  • Southwest Airlines is a low-cost carrier: expect a cheaper base fare with bags, seats and airport check-in sold separately, while United Airlines bundles more into the ticket.
  • United Airlines is a Star Alliance member, so miles and status benefits carry over to partner airlines.

Other comparisons

Allowances shown are for the basic Economy fare on most routes. Fees are the lowest published prices and change often - confirm on the official websites before booking.