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Cheap flights from San Francisco to Boston

The cheapest round trip from San Francisco to Boston that travelers found recently is $232 with a carry-on: a $232 fare on Southwest, which usually includes a carry-on. It leaves Mon, Dec 7 and comes back Fri, Dec 11.

Live prices for Mon, Dec 7 to Fri, Dec 11

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$232Cheapest round trip, carry-on included (est.)
$354Typical round trip found recently
DecemberCheapest month in the next few, from $232
14%Of these fares are nonstop

Cheapest trips travelers found recently

LeaveReturnAirlineAirportsStopsFareCarry-on (est.)TotalLive prices
Mon, Dec 7Fri, Dec 11SouthwestSJC → BOS1 stop$232Included$232Live price
Mon, Dec 14Thu, Dec 17SouthwestSJC → BOS2 stops$291Included$291Live price
Thu, Oct 22Mon, Oct 26SouthwestSFO → BOS2 stops$351Included$351Live price
Thu, Nov 5Sun, Nov 8JetBlueSFO → BOSNonstop$354Included$354Live price
Fri, Oct 16Mon, Oct 19Alaska AirlinesSFO → BOS1 stop$402Included$402Live price
Sat, Mar 6Mon, Mar 8JetBlueSFO → BOS1 stop$464Included$464Live price
Wed, Oct 14Sun, Oct 18FrontierSFO → BOS1 stop$686+$110$796Live price

Round-trip prices per person, from real fares travelers found in the last few days. Carry-on fees are our estimate for each airline, both ways. Prices change fast: check the live price before you book.

Cheapest month to fly

MonthCheapest tripFromLive prices
October 2026Thu, Oct 22 to Mon, Oct 26, 4 nights$351Live price
November 2026Thu, Nov 5 to Sun, Nov 8, 3 nights$354Live price
December 2026Mon, Dec 7 to Fri, Dec 11, 4 nights$232Live price
March 2027Sat, Mar 6 to Mon, Mar 8, 2 nights$464Live price

Bag fees on this route

What the airlines flying San Francisco to Boston usually charge for one bag each way. Budget airlines often sell the cheapest fares and charge the most for bags, so compare the total, not the fare.

AirlineCarry-on, each wayChecked bag, each way
Alaska AirlinesIncluded$40
Frontier$55$50
JetBlueIncluded$40
SouthwestIncluded$35

Our estimates: fees depend on the fare type and when you pay. Check the airline's own price when you book.

How these prices work

These are real round-trip fares that travelers found on Aviasales recently, not a live search, so they can change or sell out. Dipt adds an estimate of each airline's carry-on fee, so a cheap fare with expensive bags doesn't look cheaper than it is. "Live price" opens Dipt's live flight search for those dates, where you book with the airline or travel site you pick. Dipt may earn a commission when you book, at no extra cost to you (how Dipt makes money).

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