Itineraries flown on 20+ days in the Jun 6 – Jul 31, 2026 schedule · each leg’s record Aug 2025 – Jul 2026

No clear winner: airlines and hours on this route all land within a few points of 84% on time.

Nonstops


United	TUS	DEN	1h 59m	87%	0.5%	1,456	Flying now
Southwest	TUS	DEN	1h 55m	81%	0.6%	1,198	Flying now
Frontier	TUS	DEN	2h 00m	81%	1.2%	86	Not flying now

Best connections, one ticket

Most reliable Quickest (80%+ on time)

Ranked by chance you reach Denver on time. Total trip = scheduled departure to arrival, layover included (Denver is 1 h ahead of Tucson). Layovers up to 4 hours. Pick a connection for the details.


American Details →	TUS 05:45 → PHX 06:36AA 2622	1h 56m Phoenix	PHX 08:32 → DEN 11:29AA 1757	4h 42m	100%	89%
Southwest Details →	TUS 06:45 → LAS 08:00WN 860	55m Las Vegas	LAS 08:55 → DEN 11:50WN 247	4h 05m	96%	85%
Delta Details →	TUS 07:05 → SLC 10:11DL 3745 · flown by SkyWest	3h 09m Salt Lake City	SLC 13:20 → DEN 14:56DL 1623	6h 51m	100%	85%
United Details →	TUS 06:37 → IAH 11:13UA 4042 · flown by Mesa	1h 20m Houston	IAH 12:33 → DEN 14:17UA 2168	6h 40m	97%	84%
United Details →	TUS 15:28 → SFO 17:50UA 5583 · flown by SkyWest	2h 06m San Francisco	SFO 19:56 → DEN 23:43UA 2019	7h 15m	93%	81%
Southwest Details →	TUS 07:15 → PHX 08:05WN 1467	2h 55m Phoenix	PHX 11:00 → DEN 13:45WN 3262	5h 30m	100%	81%
Delta Details →	TUS 06:00 → ATL 12:37DL 886	1h 13m Atlanta	ATL 13:50 → DEN 15:00DL 530	8h 00m	98%	78%
Delta Details →	TUS 16:47 → LAX 18:36DL 3778 · flown by SkyWest	1h 53m Los Angeles	LAX 20:29 → DEN 23:52DL 1729	6h 06m	96%	75%

Same layover, different day-part

How often the first flight arrives too late to connect (45 min minimum), for one-ticket layovers of 45–80 minutes.

Morning

DFW · 1h 14m · leaves 05:01 6%

SEA · 1h 07m · leaves 07:10 7%

SFO · 1h 18m · leaves 09:04 19%

Afternoon and evening

SEA · 1h 16m · leaves 14:29 9%

SFO · 1h 06m · leaves 15:28 20%

Delays build through the day, so an afternoon first leg eats the layover. A short connection is fine early in the morning and a gamble later on.

Mixing airlines

One ticketMiss it and the airline rebooks you; bags go through. 45 min is enough.

Separate ticketsMiss it and you buy a new ticket. Re-check bags, clear security again: we require 90 min.


Delta DL 3745 TUS 07:05 → SLC United UA 4720 SLC 13:05 → DEN Connection details →	2h 54m	6h 46m	100%	92%
Delta DL 3502 TUS 06:20 → LAX United UA 2061 LAX 10:55 → DEN Connection details →	2h 51m	7h 07m	98%	89%
Southwest WN 860 TUS 06:45 → LAS United UA 1315 LAS 09:37 → DEN Connection details →	1h 37m	4h 56m	94%	87%

Rank all connections, any airlines →

Regional partners count as the airline that sells them: SkyWest flying Delta Connection is one Delta ticket.

How these are worked out. Makes the connection: share of the last year’s flights where the first flight arrived with at least 45 minutes to spare (90 on separate tickets). Arrives on time: first flight not cancelled × connection made × second flight not cancelled and arriving within 15 minutes. Not yet counted: the second flight also leaving late (which helps), gate-to-gate distance at the hub, and rebooking after a missed connection.

About this data: US DOT on-time records, Aug 2025 – Jul 2026, all US airlines; regional flights count under the airline that sells them. Schedules (which flights and connections exist, and their times) are as of Jun 6 – Jul 31, 2026; seasonal flights outside that window aren’t ranked. Rebuilt monthly. JSON