Flights Boston → San Francisco
As of August 2026, economy flights from Boston to San Francisco have a typical range USD 359–796, median USD 460. Full range across all 170 offers: USD 277–1349. We found 54% of 170 offers from budget carriers (around USD 410) and 46% from full-service carriers (around USD 494).
Preview snapshot — prices change. Search for live results.
Data collected by LetsFG's multi-source price checks — every airline and the major booking sites checked for this route. How we collect data →
Best offers by airline: Boston → San Francisco
Based on 170 offers · August 2026. Prices and availability change — run a live search to confirm.
Bag & seat fees: Boston → San Francisco
Add-on pricing from the cheapest available offer per airline · August 2026 · USD
| Airline | Carry-on | Checked bag | Seat selection |
|---|---|---|---|
| American Airlines | Included | USD 35 | — |
| United Airlines | Included | USD 35 | — |
| Southwest Airlines | Included | Included | — |
| JetBlue | Included | USD 134 | — |
| AS | — | USD 35 | — |
Fees are estimates from the prices we checked and may not reflect your specific itinerary, booking class, or payment method. Run a live search for exact pricing.
How much do flights from Boston to San Francisco cost?
Based on 170 offers · August 2026
Boston to San Francisco flights ranged from USD 277 to USD 1349 across 170 offers analyzed in August 2026. Two fare clusters detected: budget fares around 437 and premium fares around 759 The chart below shows how prices distributed across all 170 offers.
These 170 offers (August 2026) span multiple departure dates and booking windows — your travel dates may fall anywhere in this distribution. Only a live search shows where your specific trip lands.
50% of offers priced between USD 392 and USD 621
What hidden fees do Boston to San Francisco flights charge?
Ancillary fees — bags, seat selection, and payment surcharges — can add 10–25% to the base fare on Boston to San Francisco routes. The breakdown below is based on 170 offers analyzed in August 2026.
| Carrier | Avg fee (USD) | % of base fare |
|---|---|---|
| AA | 47 | 10% |
| UA | 88 | 24% |
| WN | 0 | 0% |
| B6 | 129 | 28% |
| AS | 45 | 11% |
B6: base ~USD 280 + fees USD 129 = ~USD 409 total. Alaska Airlines: base ~USD 365 + fees USD 45 = ~USD 410 total.
B6's USD 129 ancillary fees narrow the gap with Alaska Airlines's lower-fee model — the USD 85 base difference shrinks to USD 1 after fees. Always compare total cost, not just the advertised base fare.
Estimates based on median total minus average ancillary fee. Actual base fares vary by itinerary.Fee levels vary significantly across carriers on this route — some carriers charge 50%+ above the base fare in ancillary fees.
Run your search to see itemized fees for your itineraryWhich airline is cheapest from Boston to San Francisco?
8 airlines flew Boston to San Francisco in this dataset. The route shows a clear split between low-cost and full-service carriers. Knowing the airline isn't enough — the typical fare range below shows how far prices swing on each one. Median and range include all fees we recorded.
Even on the cheapest airline (Southwest Airlines), fares ranged USD 347–356 in this snapshot. Your exact price depends on your dates and how far ahead you book — run a live search to see your number →
| Airline | Offers | Typical range (USD) | Median (USD) | Fees (USD) |
|---|---|---|---|---|
 Southwest Airlines | 5 | 347–356 | 347 | 0 (0%) |
 United Airlines | 25 | 359–412 | 359 | 88 (25%) |
 B6 | 59 | 392–568 | 409 | 129 (32%) |
 Alaska Airlines | 2 | — | 410 | 45 (11%) |
 American Airlines | 38 | 278–563 | 494 | 47 (10%) |
 Southwest | 34 | 757–817 | 796 | n/a |
 Delta | 1 | — | 893 | n/a |
 Alaska | 6 | 855–1307 | 1187 | n/a |
Where do the best Boston → San Francisco prices come from?
We checked direct airlines, travel agencies, and meta-search for this route. On this route the lowest median came from meta-search sources, but the cheapest channel shifts by route and date — which is exactly why a live search across all of them wins.
We compare every airline and the major booking sites but never disclose which — that's our edge. Prices are the ones we observed and aren't official data from any platform. Run a live search and we bring you the cheapest, wherever it is.
Key facts: Boston to San Francisco flights
- Full-service carriers on Boston–San Francisco cost 1.3x more than budget airlines (USD 669 vs USD 517 median; overall median USD 460).
- B6 charges 2.9x more in ancillary fees than AS — USD 129 vs USD 45 avg per booking.
- The same route priced USD 493 apart depending on where it was booked — the lowest median was USD 303. We search every airline and the major booking sites at once so you always see that lowest price.
Frequently asked questions
- How much does a flight from Boston to San Francisco cost?
- Based on 170 offers analyzed, Boston to San Francisco flights range from USD 277 to USD 1349, with a median price of USD 460. Search for your specific dates →
- What hidden fees should I expect on Boston to San Francisco flights?
- On average, ancillary fees (bags, seat selection) add USD 91 to the base fare on Boston to San Francisco flights. See itemized fees for your itinerary →
- Which airline is cheapest on Boston to San Francisco including all fees?
- Southwest Airlines has the lowest median fare on Boston to San Francisco at USD 347 (median across 5 offers in our snapshot). Check which airline wins on your dates →
- Which booking site has the cheapest Boston–San Francisco flights?
- It depends on your dates — no single site is always cheapest. We search every airline and the major booking sites at once (travel agencies and meta-search included) and surface whichever is lowest; the best median in this snapshot was USD 303. Run a live search and we'll find the cheapest for you →
- Why do prices vary so much on Boston to San Francisco routes?
- Boston to San Francisco has 8 airlines competing, creating a price range from USD 277 to USD 1349 across 170 offers. There are two distinct fare clusters on this route: budget options and premium fares. Find where your trip lands in the distribution →
8 airlines, two price clusters — find which fits your budget
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