United Airlines
vol
UA 521:
Multiple routes
HORAIRES DES VOLS
Vols directs:
United Airlines UA521
Effective 2026-03-29 through 2026-04-29
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 2:15, non-stop
Airbus A319 (319)
Airbus A319 (319)
Vols directs:
United Airlines UA521
Effective 2026-04-30 through 2026-05-20
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 2:15, non-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols directs:
United Airlines UA521
Effective from 2026-05-21
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 2:15, non-stop
Airbus A319 (319)
Airbus A319 (319)
Vols directs:
United Airlines UA521
Effective 2026-03-05 through 2026-03-27
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
Ven
Sam
-
-
Dim
-
-
Duration: 2:28, non-stop
Airbus A320 (320)
Airbus A320 (320)
Vols directs:
United Airlines UA521
Effective 2026-03-07 through 2026-03-28
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
Dim
-
-
Duration: 2:28, non-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols directs:
United Airlines UA521
Effective 2026-03-08 through 2026-03-25
Lun
Mar
Mer
Jeu
-
-
Ven
-
-
Sam
-
-
Dim
Duration: 2:28, non-stop
Airbus A319 (319)
Airbus A319 (319)
Vols directs:
United Airlines UA521
Effective 2026-02-12 through 2026-03-04
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 2:30, non-stop
Boeing 737-800 (738)
Boeing 737-800 (738)
Vols directs:
United Airlines UA521
Effective 2026-01-10 through 2026-02-07
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
Dim
-
-
Duration: 2:28, non-stop
Airbus A320 (320)
Airbus A320 (320)
Vols directs:
United Airlines UA521
Effective 2026-01-07 through 2026-02-11
Lun
Mar
-
-
Mer
Jeu
Ven
Sam
-
-
Dim
-
-
Duration: 1:31, non-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols directs:
United Airlines UA521
Effective 2026-01-11 through 2026-02-08
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
-
-
Dim
Duration: 1:31, non-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols directs:
United Airlines UA521
Effective 2026-01-06 through 2026-02-10
Lun
-
-
Mar
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
-
-
Dim
-
-
Duration: 1:30, non-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols directs:
United Airlines UA521
Effective 2026-03-29 through 2026-04-29
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 3:57, non-stop
Boeing 737-900 (739)
Boeing 737-900 (739)
Vols directs:
United Airlines UA521
Effective 2026-04-30 through 2026-05-20
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 3:45, non-stop
Boeing 737 MAX 8 (7M8)
Boeing 737 MAX 8 (7M8)
Vols directs:
United Airlines UA521
Effective from 2026-05-21
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 3:45, non-stop
Boeing 737-800 (738)
Boeing 737-800 (738)
Vols directs:
United Airlines UA521
Effective 2026-03-05 through 2026-03-27
Lun
Mar
-
-
Mer
Jeu
Ven
Sam
-
-
Dim
Duration: 3:48, non-stop
Boeing 737 MAX 8 (7M8)
Boeing 737 MAX 8 (7M8)
Vols directs:
United Airlines UA521
Effective 2026-03-07 through 2026-03-28
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
Dim
-
-
Duration: 3:48, non-stop
Boeing 737-800 (738)
Boeing 737-800 (738)
Vols directs:
United Airlines UA521
Effective 2026-02-12 through 2026-03-04
Lun
Mar
Mer
Jeu
Ven
Sam
-
-
Dim
-
-
Duration: 3:29, non-stop
Boeing 737-800 (738)
Boeing 737-800 (738)
Vols directs:
United Airlines UA521
Valid until 2026-01-04
Lun
Mar
Mer
Jeu
Ven
Sam
-
-
Dim
Duration: 3:17, non-stop
Boeing 737 MAX 8 (7M8)
Boeing 737 MAX 8 (7M8)
Vols directs:
United Airlines UA521
Operates only on 2026-01-05
Lun
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
-
-
Dim
-
-
Duration: 3:17, non-stop
Boeing 737-900 (739)
Boeing 737-900 (739)
Vols directs:
United Airlines UA521
Valid until 2026-01-03
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
Dim
-
-
Duration: 3:17, non-stop
Boeing 737-900 (739)
Boeing 737-900 (739)
Vols indirects:
United Airlines UA521
Effective 2026-03-29 through 2026-04-29
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 7:47, 1-stop
Airbus A319 (319)
Airbus A319 (319)
Vols indirects:
United Airlines UA521
Effective 2026-04-30 through 2026-05-20
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 7:35, 1-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols indirects:
United Airlines UA521
Effective from 2026-05-21
Lun
Mar
Mer
Jeu
Ven
Sam
Dim
Duration: 7:35, 1-stop
Airbus A319 (319)
Airbus A319 (319)
Vols indirects:
United Airlines UA521
Effective 2026-03-05 through 2026-03-27
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
Ven
Sam
-
-
Dim
-
-
Duration: 7:33, 1-stop
Airbus A320 (320)
Airbus A320 (320)
Vols indirects:
United Airlines UA521
Effective 2026-03-07 through 2026-03-28
Lun
-
-
Mar
-
-
Mer
-
-
Jeu
-
-
Ven
-
-
Sam
Dim
-
-
Duration: 7:33, 1-stop
Boeing 737-700 (73G)
Boeing 737-700 (73G)
Vols indirects:
United Airlines UA521
Effective 2026-03-08 through 2026-03-25
Lun
Mar
-
-
Mer
Jeu
-
-
Ven
-
-
Sam
-
-
Dim
Duration: 7:33, 1-stop
Airbus A319 (319)
Airbus A319 (319)
Vols indirects:
United Airlines UA521
Effective 2026-02-12 through 2026-03-04
Lun
Mar
Mer
Jeu
Ven
Sam
-
-
Dim
-
-
Duration: 7:10, 1-stop
Boeing 737-800 (738)
Boeing 737-800 (738)
This flight number is listed as serving the following routes:
- Atlanta (ATL) - Boston Logan (BOS)
- Atlanta (ATL) - Houston George Bush (IAH)
- Atlanta (ATL) - New York LaGuardia (LGA)
- Boston Logan (BOS) - Newark Liberty, New York (EWR)
- Houston George Bush (IAH) - Boston Logan (BOS)
- Houston George Bush (IAH) - New York LaGuardia (LGA)
- Newark Liberty, New York (EWR) - Fort Lauderdale (FLL)
- Saint Louis (STL) - Houston George Bush (IAH)