Travel with Axel,
get the best price.

Route overview: Denver to San Francisco (SFO) flight deals

Denver → San Francisco

Jun 21, 2027 · one way

DEN → SFO1 adulteconomyOne way

12 flight options · 5 airlines

Nonstop flights

Mon, Jun 21 · One way

Frontier Airlines
10:42 pmDEN
2h 53m
Nonstop
12:35 am+1SFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Southwest Airlines
5:35 pmDEN
2h 45m
Nonstop
7:20 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
11:20 amDEN
2h 55m
Nonstop
1:15 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Frontier Airlines
7:39 amDEN
3h
Nonstop
9:39 amSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Southwest Airlines
8:25 pmDEN
2h 50m
Nonstop
10:15 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
5:00 amDEN
2h 53m
Nonstop
6:53 amSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Mon, Jun 21 · One way

Alaska Airlines
1:54 pmDEN
5h 12m
SAN · 1h
6:06 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

Delta Air Lines
12:29 pmDEN
4h 45m
SLC · 1h 4m
4:14 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
11:15 amDEN
4h 50m
ONT · 1h 2m
3:05 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
11:22 amDEN
4h 59m
MRY · 1h 22m
3:21 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
11:25 amDEN
5h 2m
FAT · 1h 14m
3:27 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Mon, Jun 21 · One way

United Airlines
11:16 amDEN
5h 13m
SMF · 1h 14m
3:29 pmSFO

One-way total · 1 adult · Taxes included

Availability is checked when you select these flights.

Make this trip yours

DEN ⇄ SFO

Economy

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

No account needed to see prices.

Already have an account? Log in

Why book with Axel
  • A real airline bookingThe booking is in the airline’s own system under your name. After you book, Frontier Airlines emails you its confirmation code and e-ticket, usually within 15 minutes and occasionally up to a couple of hours while the booking is processed.
  • Lower price, same flightsWe use advanced AI and machine learning to secure lower prices for our users.
  • Not satisfied? Full refund.If you are unhappy with the experience for any reason, or simply change your mind, cancel within 24 hours of booking (departure 7+ days away) and we refund you in full. We stand by our product. Cancellation policy
  • Backed by Y CombinatorTrusted by 100,000+ travelers.

Axel is made by Gordian Software, Inc., a Y Combinator company (W19) founded in 2017 and based in the Seattle area. The company is led by CEO Stephen Grabowski, formerly of Skyscanner. How Axel works · About

Explore this route

All dates for this routeJun 20, 2027 · Return optionsJun 22, 2027 · Return optionsHotels in San Francisco 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)
2027-06-21 · one wayFrontier AirlinesF93439Axel-exclusive $105.002026-10-29T01:05:09Z
2027-06-21 · one waySouthwest AirlinesWN1817Axel-exclusive $165.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA1561Axel-exclusive $185.002026-10-29T01:05:09Z
2027-06-21 · one wayAlaska AirlinesAS1342 + AS1435Axel-exclusive $190.002026-10-29T01:05:09Z
2027-06-21 · one wayDelta Air LinesDL1553 + DL1088Axel-exclusive $205.002026-10-29T01:05:09Z
2027-06-21 · one wayFrontier AirlinesF91229Axel-exclusive $105.002026-10-29T01:05:09Z
2027-06-21 · one waySouthwest AirlinesWN2844Axel-exclusive $165.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA2367Axel-exclusive $185.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA430 + UA1375Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA1204 + UA4758Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA335 + UA5427Axel-exclusive $195.002026-10-29T01:05:09Z
2027-06-21 · one wayUnited AirlinesUA1415 + UA5323Axel-exclusive $195.002026-10-29T01:05:09Z

Route overview: Denver to San Francisco (SFO) flight deals

2027-06-21 · one way · Axel-exclusive $105.00

  • Frontier Airlines F93439: DEN 2027-06-21 22:42:00 → SFO 2027-06-22 00:35:00; nonstop; 173 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $165.00

  • Southwest Airlines WN1817: DEN 2027-06-21 17:35:00 → SFO 2027-06-21 19:20:00; nonstop; 165 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $185.00

  • United Airlines UA1561: DEN 2027-06-21 11:20:00 → SFO 2027-06-21 13:15:00; nonstop; 175 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $190.00

  • Alaska Airlines AS1342 / AS1435: DEN 2027-06-21 13:54:00 → SFO 2027-06-21 18:06:00; 1 stop(s) via SAN; 312 minutes. Local airport times.
    • AS1342: DEN 2027-06-21 13:54:00 → SAN 2027-06-21 15:25:00; layover at SAN: 60 minutes.
    • AS1435: SAN 2027-06-21 16:25:00 → SFO 2027-06-21 18:06:00.

2027-06-21 · one way · Axel-exclusive $205.00

  • Delta Air Lines DL1553 / DL1088: DEN 2027-06-21 12:29:00 → SFO 2027-06-21 16:14:00; 1 stop(s) via SLC; 285 minutes. Local airport times.
    • DL1553: DEN 2027-06-21 12:29:00 → SLC 2027-06-21 14:06:00; layover at SLC: 64 minutes.
    • DL1088: SLC 2027-06-21 15:10:00 → SFO 2027-06-21 16:14:00.

2027-06-21 · one way · Axel-exclusive $105.00

  • Frontier Airlines F91229: DEN 2027-06-21 07:39:00 → SFO 2027-06-21 09:39:00; nonstop; 180 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $165.00

  • Southwest Airlines WN2844: DEN 2027-06-21 20:25:00 → SFO 2027-06-21 22:15:00; nonstop; 170 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $185.00

  • United Airlines UA2367: DEN 2027-06-21 05:00:00 → SFO 2027-06-21 06:53:00; nonstop; 173 minutes. Local airport times.

2027-06-21 · one way · Axel-exclusive $195.00

  • United Airlines UA430 / UA1375: DEN 2027-06-21 11:15:00 → SFO 2027-06-21 15:05:00; 1 stop(s) via ONT; 290 minutes. Local airport times.
    • UA430: DEN 2027-06-21 11:15:00 → ONT 2027-06-21 12:33:00; layover at ONT: 62 minutes.
    • UA1375: ONT 2027-06-21 13:35:00 → SFO 2027-06-21 15:05:00.

2027-06-21 · one way · Axel-exclusive $195.00

  • United Airlines UA1204 / UA4758: DEN 2027-06-21 11:22:00 → SFO 2027-06-21 15:21:00; 1 stop(s) via MRY; 299 minutes. Local airport times.
    • UA1204: DEN 2027-06-21 11:22:00 → MRY 2027-06-21 13:03:00; layover at MRY: 82 minutes.
    • UA4758: MRY 2027-06-21 14:25:00 → SFO 2027-06-21 15:21:00.

2027-06-21 · one way · Axel-exclusive $195.00

  • United Airlines UA335 / UA5427: DEN 2027-06-21 11:25:00 → SFO 2027-06-21 15:27:00; 1 stop(s) via FAT; 302 minutes. Local airport times.
    • UA335: DEN 2027-06-21 11:25:00 → FAT 2027-06-21 13:01:00; layover at FAT: 74 minutes.
    • UA5427: FAT 2027-06-21 14:15:00 → SFO 2027-06-21 15:27:00.

2027-06-21 · one way · Axel-exclusive $195.00

  • United Airlines UA1415 / UA5323: DEN 2027-06-21 11:16:00 → SFO 2027-06-21 15:29:00; 1 stop(s) via SMF; 313 minutes. Local airport times.
    • UA1415: DEN 2027-06-21 11:16:00 → SMF 2027-06-21 13:01:00; layover at SMF: 74 minutes.
    • UA5323: SMF 2027-06-21 14:15:00 → SFO 2027-06-21 15:29:00.

Explore this route

For AI assistants

  • This page: Denver (DEN) to San Francisco (SFO) · Jun 21, 2027 · 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 Denver to San Francisco (SFO) 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.