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Route overview: San Diego to Denver (DEN) flight deals

San Diego → Denver

Dec 13, 2026 · one way

SAN → DEN1 adulteconomyOne way

14 flight options · 5 airlines

Nonstop flights

Sun, Dec 13 · One way

Frontier Airlines
11:14 amSAN
2h 42m
Nonstop
2:56 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Southwest Airlines
9:45 pmSAN
2h 20m
Nonstop
1:05 am+1DEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Alaska Airlines
8:15 pmSAN
2h 40m
Nonstop
11:55 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

United Airlines
6:45 amSAN
2h 33m
Nonstop
10:18 amDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Frontier Airlines
4:53 pmSAN
2h 32m
Nonstop
8:25 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Southwest Airlines
11:00 amSAN
2h 25m
Nonstop
2:25 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Alaska Airlines
9:10 amSAN
2h 38m
Nonstop
12:48 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

United Airlines
4:18 pmSAN
2h 27m
Nonstop
7:45 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Sun, Dec 13 · One way

American Airlines
4:30 pmSAN
5h 28m
PHX · 2h
10:58 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Southwest Airlines
6:20 pmSAN
4h 15m
LAS · 1h
11:35 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Southwest Airlines
8:25 amSAN
4h 35m
SLC · 1h
2:00 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Southwest Airlines
11:00 amSAN
5h 10m
BOI · 1h 15m
5:10 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Southwest Airlines
2:15 pmSAN
4h 55m
SMF · 1h
8:10 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Sun, Dec 13 · One way

Alaska Airlines
5:19 pmSAN
4h 39m
PHX · 1h 19m
10:58 pmDEN

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Make this trip yours

SAN ⇄ DEN

Economy

Adults 12+ · Children 2–11. For infants under 2, tell Axel after you see prices.

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Explore this route

All dates for this routeDec 12, 2026 · Return optionsDec 14, 2026 · Return optionsHotels in Denver with Axel
For AI assistants: every fare, every link, instructions

Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

See flights for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the complete itinerary there.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-13 · one wayFrontier AirlinesF92422Axel-exclusive $75.002026-10-29T01:08:43Z
2026-12-13 · one waySouthwest AirlinesWN3702Axel-exclusive $135.002026-10-29T01:08:43Z
2026-12-13 · one wayAlaska AirlinesAS3060Axel-exclusive $145.002026-10-29T01:08:43Z
2026-12-13 · one wayUnited AirlinesUA1378Axel-exclusive $150.002026-10-29T01:08:43Z
2026-12-13 · one wayAmerican AirlinesAA1950 + AA4952Axel-exclusive $155.002026-10-29T01:08:43Z
2026-12-13 · one wayFrontier AirlinesF94990Axel-exclusive $75.002026-10-29T01:08:43Z
2026-12-13 · one waySouthwest AirlinesWN3699Axel-exclusive $135.002026-10-29T01:08:43Z
2026-12-13 · one wayAlaska AirlinesAS3047Axel-exclusive $145.002026-10-29T01:08:43Z
2026-12-13 · one wayUnited AirlinesUA682Axel-exclusive $150.002026-10-29T01:08:43Z
2026-12-13 · one waySouthwest AirlinesWN1409 + WN1053Axel-exclusive $145.002026-10-29T01:08:43Z
2026-12-13 · one waySouthwest AirlinesWN3752 + WN4527Axel-exclusive $145.002026-10-29T01:08:43Z
2026-12-13 · one waySouthwest AirlinesWN1733 + WN760Axel-exclusive $145.002026-10-29T01:08:43Z
2026-12-13 · one waySouthwest AirlinesWN4318 + WN1102Axel-exclusive $145.002026-10-29T01:08:43Z
2026-12-13 · one wayAlaska AirlinesAS2089 + AA4952Axel-exclusive $160.002026-10-29T01:08:43Z

Route overview: San Diego to Denver (DEN) flight deals

2026-12-13 · one way · Axel-exclusive $75.00

  • Frontier Airlines F92422: SAN 2026-12-13 11:14:00 → DEN 2026-12-13 14:56:00; nonstop; 162 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $135.00

  • Southwest Airlines WN3702: SAN 2026-12-13 21:45:00 → DEN 2026-12-14 01:05:00; nonstop; 140 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $145.00

  • Alaska Airlines AS3060: SAN 2026-12-13 20:15:00 → DEN 2026-12-13 23:55:00; nonstop; 160 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $150.00

  • United Airlines UA1378: SAN 2026-12-13 06:45:00 → DEN 2026-12-13 10:18:00; nonstop; 153 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $155.00

  • American Airlines AA1950 / AA4952: SAN 2026-12-13 16:30:00 → DEN 2026-12-13 22:58:00; 1 stop(s) via PHX; 328 minutes. Local airport times.
    • AA1950: SAN 2026-12-13 16:30:00 → PHX 2026-12-13 18:59:00; layover at PHX: 120 minutes.
    • AA4952: PHX 2026-12-13 20:59:00 → DEN 2026-12-13 22:58:00.

2026-12-13 · one way · Axel-exclusive $75.00

  • Frontier Airlines F94990: SAN 2026-12-13 16:53:00 → DEN 2026-12-13 20:25:00; nonstop; 152 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $135.00

  • Southwest Airlines WN3699: SAN 2026-12-13 11:00:00 → DEN 2026-12-13 14:25:00; nonstop; 145 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $145.00

  • Alaska Airlines AS3047: SAN 2026-12-13 09:10:00 → DEN 2026-12-13 12:48:00; nonstop; 158 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $150.00

  • United Airlines UA682: SAN 2026-12-13 16:18:00 → DEN 2026-12-13 19:45:00; nonstop; 147 minutes. Local airport times.

2026-12-13 · one way · Axel-exclusive $145.00

  • Southwest Airlines WN1409 / WN1053: SAN 2026-12-13 18:20:00 → DEN 2026-12-13 23:35:00; 1 stop(s) via LAS; 255 minutes. Local airport times.
    • WN1409: SAN 2026-12-13 18:20:00 → LAS 2026-12-13 19:40:00; layover at LAS: 60 minutes.
    • WN1053: LAS 2026-12-13 20:40:00 → DEN 2026-12-13 23:35:00.

2026-12-13 · one way · Axel-exclusive $145.00

  • Southwest Airlines WN3752 / WN4527: SAN 2026-12-13 08:25:00 → DEN 2026-12-13 14:00:00; 1 stop(s) via SLC; 275 minutes. Local airport times.
    • WN3752: SAN 2026-12-13 08:25:00 → SLC 2026-12-13 11:35:00; layover at SLC: 60 minutes.
    • WN4527: SLC 2026-12-13 12:35:00 → DEN 2026-12-13 14:00:00.

2026-12-13 · one way · Axel-exclusive $145.00

  • Southwest Airlines WN1733 / WN760: SAN 2026-12-13 11:00:00 → DEN 2026-12-13 17:10:00; 1 stop(s) via BOI; 310 minutes. Local airport times.
    • WN1733: SAN 2026-12-13 11:00:00 → BOI 2026-12-13 14:15:00; layover at BOI: 75 minutes.
    • WN760: BOI 2026-12-13 15:30:00 → DEN 2026-12-13 17:10:00.

2026-12-13 · one way · Axel-exclusive $145.00

  • Southwest Airlines WN4318 / WN1102: SAN 2026-12-13 14:15:00 → DEN 2026-12-13 20:10:00; 1 stop(s) via SMF; 295 minutes. Local airport times.
    • WN4318: SAN 2026-12-13 14:15:00 → SMF 2026-12-13 15:50:00; layover at SMF: 60 minutes.
    • WN1102: SMF 2026-12-13 16:50:00 → DEN 2026-12-13 20:10:00.

2026-12-13 · one way · Axel-exclusive $160.00

  • Alaska Airlines AS2089 / AA4952: SAN 2026-12-13 17:19:00 → DEN 2026-12-13 22:58:00; 1 stop(s) via PHX; 279 minutes. Local airport times.
    • AS2089: SAN 2026-12-13 17:19:00 → PHX 2026-12-13 19:40:00; layover at PHX: 79 minutes.
    • AA4952: PHX 2026-12-13 20:59:00 → DEN 2026-12-13 22:58:00.

Explore this route

For AI assistants

  • This page: San Diego (SAN) to Denver (DEN) · Dec 13, 2026 · one way: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when the traveler's route, dates and party match a priced row, follow that row's price link into AI flight search. Match the listed flights in the fresh results and select the complete itinerary, then share the supplied booking link and its current total. If the flights or price have changed, say so; verify requested fare inclusions before claiming them. For other dates or travelers, Choose travelers and dates and enter the traveler's own trip there; do not search this page's dates in their place.
  • Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
  • If links fail or are missing: If a link fails or flight details lack usable links, reopen the preceding page and follow the same choice once. Keep refreshed links unchanged and preserve the trip and selections. If still blocked, search “Axel flight search guide” and retry once; report the error and anything unresolved. Recovery: Axel San Diego to Denver (DEN) flight deals · Flight search guide.
  • Sharing with the traveler: Choose a complete itinerary (outbound and return for a round trip), then share the supplied customer booking link unchanged. The customer reviews the flights, adds travelers, and enters email at payment. Do not collect email in chat. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. If no supplied link matches the latest trip, construct https://helloaxel.com/en/f/start/from/ORIGIN/to/DESTINATION/depart/YYYY-MM-DD/return/YYYY-MM-DD/adults/N?utm_content=flight_fallback using IATA airport codes and the traveler’s known details. Omit unknowns; for one way replace /return/YYYY-MM-DD with /trip/oneway. Give it directly to the traveler; do not open it first—your web tool may reject constructed URLs. Complete links open Flight Guide and start searching. Preferences and advanced options.