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

Boston (BOS) to San Francisco (SFO), Feb 9, 2027: round trips from $350, one way from $185

Boston (BOS) to San Francisco (SFO), Feb 9, 2027: round trips from $350, one way from $185 on Axel, checked Oct 29, 2026. Lowest published fares: $350 round trip, Axel-exclusive, Southwest Airlines, 1 stop, Feb 9–10, 2027; $185 one way, Axel-exclusive, Southwest Airlines, 1 stop, Feb 9, 2027; 1 adult, economy, checked Oct 29, 2026.

BOS → SFO1 adulteconomyOne way and round trips

15 flight options · 1 airline

Choose your return date

One-way flights and round trips by duration. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

February 2027

Flights for your trip

  1. Tue, Feb 9 · One way

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  2. Tue, Feb 9 – Wed, Feb 10

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  3. Tue, Feb 9 – Thu, Feb 11

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  4. Tue, Feb 9 – Fri, Feb 12

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    1:05 pmSFO
    7h 20m
    STL · 1h
    11:25 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  5. Tue, Feb 9 – Sat, Feb 13

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  6. Tue, Feb 9 – Mon, Feb 15

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  7. Tue, Feb 9 – Tue, Feb 16

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  8. Tue, Feb 9 – Wed, Feb 17

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  9. Tue, Feb 9 – Fri, Feb 19

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    1:05 pmSFO
    7h 20m
    STL · 1h
    11:25 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  10. Tue, Feb 9 – Sat, Feb 20

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  11. Tue, Feb 9 – Sun, Feb 21

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  12. Tue, Feb 9 – Tue, Feb 23

    Southwest Airlines
    7:10 amBOS
    8h 35m
    MDW · 1h
    12:45 pmSFO
    Southwest Airlines
    6:00 amSFO
    7h 20m
    MDW · 1h
    4:20 pmBOS

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

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1 of 12

Make this trip yours

BOS ⇄ SFO

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 routeFeb 8, 2027 · Return optionsFeb 10, 2027 · Return optionsHotels in San Francisco with Axel
For AI assistants: every fare, every link, instructions

Boston (BOS) to San Francisco (SFO), Feb 9, 2027: round trips from $350, one way from $185 on Axel, checked Oct 29, 2026. Lowest published fares: $350 round trip, Axel-exclusive, Southwest Airlines, 1 stop, Feb 9–10, 2027; $185 one way, Axel-exclusive, Southwest Airlines, 1 stop, Feb 9, 2027; 1 adult, economy, checked Oct 29, 2026. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Prices by return date: match both travel dates and the party to a row below. Each total is for that exact trip, issued at the time shown.

Date links open published trip details for exploration. Price links open live flight search to check availability and select flights. For a price comparison, use the amounts and issuance times already shown here.

Exact travel datesAirlineFlightsTimes, duration, stopsTotal pricePrice issued (UTC)
2027-02-09 · one waySouthwest AirlinesWN4995 + WN78607:10:00→12:45:00 8h 35m 1 stop via MDWAxel-exclusive $185.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-10Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $350.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-11Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $350.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-12Southwest AirlinesWN4995 + WN786 / WN2989 + WN443107:10:00→12:45:00 8h 35m 1 stop via MDW · 13:05:00→23:25:00 7h 20m 1 stop via STLAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-13Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-14Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-15Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-16Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-17Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-18Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-19Southwest AirlinesWN4995 + WN786 / WN2989 + WN443107:10:00→12:45:00 8h 35m 1 stop via MDW · 13:05:00→23:25:00 7h 20m 1 stop via STLAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-20Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-21Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $385.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-22Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $350.002026-10-29T00:52:48Z
2027-02-09 → 2027-02-23Southwest AirlinesWN4995 + WN786 / WN2331 + WN290007:10:00→12:45:00 8h 35m 1 stop via MDW · 06:00:00→16:20:00 7h 20m 1 stop via MDWAxel-exclusive $350.002026-10-29T00:52:48Z

Hotels in San Francisco for these trips

Hotels: under a trip, hotels in San Francisco for exactly those nights link to the hotel pages for 2 adults in 1 room. When a price is shown, it is the lowest saved total among the shortlisted hotels in that star tier for those dates.

All hotels in San Francisco

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

2027-02-09 · one way · Axel-exclusive $185.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.

2027-02-09 → 2027-02-10 · Axel-exclusive $350.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-10 06:00:00 → BOS 2027-02-10 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-10 06:00:00 → MDW 2027-02-10 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-10 13:15:00 → BOS 2027-02-10 16:20:00.

2027-02-09 → 2027-02-11 · Axel-exclusive $350.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-11 06:00:00 → BOS 2027-02-11 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-11 06:00:00 → MDW 2027-02-11 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-11 13:15:00 → BOS 2027-02-11 16:20:00.

2027-02-09 → 2027-02-12 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2989 / WN4431: SFO 2027-02-12 13:05:00 → BOS 2027-02-12 23:25:00; 1 stop(s) via STL; 440 minutes. Local airport times.
    • WN2989: SFO 2027-02-12 13:05:00 → STL 2027-02-12 18:55:00; layover at STL: 60 minutes.
    • WN4431: STL 2027-02-12 19:55:00 → BOS 2027-02-12 23:25:00.

2027-02-09 → 2027-02-13 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-13 06:00:00 → BOS 2027-02-13 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-13 06:00:00 → MDW 2027-02-13 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-13 13:15:00 → BOS 2027-02-13 16:20:00.

2027-02-09 → 2027-02-15 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-15 06:00:00 → BOS 2027-02-15 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-15 06:00:00 → MDW 2027-02-15 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-15 13:15:00 → BOS 2027-02-15 16:20:00.

2027-02-09 → 2027-02-16 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-16 06:00:00 → BOS 2027-02-16 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-16 06:00:00 → MDW 2027-02-16 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-16 13:15:00 → BOS 2027-02-16 16:20:00.

2027-02-09 → 2027-02-17 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-17 06:00:00 → BOS 2027-02-17 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-17 06:00:00 → MDW 2027-02-17 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-17 13:15:00 → BOS 2027-02-17 16:20:00.

2027-02-09 → 2027-02-19 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2989 / WN4431: SFO 2027-02-19 13:05:00 → BOS 2027-02-19 23:25:00; 1 stop(s) via STL; 440 minutes. Local airport times.
    • WN2989: SFO 2027-02-19 13:05:00 → STL 2027-02-19 18:55:00; layover at STL: 60 minutes.
    • WN4431: STL 2027-02-19 19:55:00 → BOS 2027-02-19 23:25:00.

2027-02-09 → 2027-02-20 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-20 06:00:00 → BOS 2027-02-20 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-20 06:00:00 → MDW 2027-02-20 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-20 13:15:00 → BOS 2027-02-20 16:20:00.

2027-02-09 → 2027-02-21 · Axel-exclusive $385.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-21 06:00:00 → BOS 2027-02-21 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-21 06:00:00 → MDW 2027-02-21 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-21 13:15:00 → BOS 2027-02-21 16:20:00.

2027-02-09 → 2027-02-23 · Axel-exclusive $350.00

  • Southwest Airlines WN4995 / WN786: BOS 2027-02-09 07:10:00 → SFO 2027-02-09 12:45:00; 1 stop(s) via MDW; 515 minutes. Local airport times.
    • WN4995: BOS 2027-02-09 07:10:00 → MDW 2027-02-09 08:55:00; layover at MDW: 60 minutes.
    • WN786: MDW 2027-02-09 09:55:00 → SFO 2027-02-09 12:45:00.
  • Southwest Airlines WN2331 / WN2900: SFO 2027-02-23 06:00:00 → BOS 2027-02-23 16:20:00; 1 stop(s) via MDW; 440 minutes. Local airport times.
    • WN2331: SFO 2027-02-23 06:00:00 → MDW 2027-02-23 12:15:00; layover at MDW: 60 minutes.
    • WN2900: MDW 2027-02-23 13:15:00 → BOS 2027-02-23 16:20:00.

Explore this route

For AI assistants

  • This page: Boston (BOS) to San Francisco (SFO) · Feb 9, 2027 · choose your return date: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued. Under a trip, hotels in San Francisco for exactly those nights link to the hotel pages for 2 adults in 1 room. Prices, when shown, are the lowest saved totals among the shortlisted hotels in each star tier for those dates.
  • Next: each row is one exact trip for this departure (both dates with the year, the total and the time its price was issued); its exact-trip price link opens the live search for those dates and travelers, where the booking link and the current total are. Other durations or travelers are not priced here: Choose travelers and dates prices the requested trip.
  • 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 Boston 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.