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Boston → San Francisco flights

Boston–SFO fares have a median of $147 over a 12-day sample, with most fares bunched between $117 and $149.

Fares cluster near $147 — little room to game timing

Key takeaways

Median fare sits at $147, close to the observed high of $149
Bottom quartile ($117) shows occasional dips worth watching for
Spread of 46% looks wide, but it's driven by a single low outlier at $102
Three-quarters of fares fall in a narrow $117–$149 band
Sample size is thin at 12 snapshots, so patterns should be treated as directional, not definitive

30-day price trend

BOS → SFO · cheapest cached fare per day · last 13 days · ↓ 32%

$102 low$149 high

See full numbers and stats on the BOS → SFO price history page.

The full picture

The data shows a median fare of $147 for Boston to San Francisco, with most observed prices packed tightly between $117 (25th percentile) and $149 (75th percentile and also the high). That's a compressed range for the bulk of fares — the real story in the 46% spread is a single low snapshot of $102, which pulls the headline spread number wider than what travelers are likely to actually encounter on a typical search day.

With only 12 snapshots, we can't responsibly point to a specific booking window where prices reliably soften — the sample is too thin to separate signal from noise. What we can say is that the overwhelming majority of fares cluster near the top of the range, suggesting that $140–149 is the realistic price most travelers should expect to pay, and that $117 or below represents a genuine deal if you see it, not the norm.

No carrier or day-of-week pattern is visible in this dataset, so we can't make claims about specific airlines or departure days driving the pricing. The practical takeaway: budget around $147, treat anything near $117 as a good fare worth booking quickly, and don't expect dramatic swings — this route looks like it holds a fairly stable price floor. The honest caveat here is that with just 12 data points, this snapshot captures a narrow slice of time and may not reflect seasonal shifts, fare sales, or longer-term booking-curve behavior.

Ready to look at fares?

Search BOS → SFO on Aviasales →See the price history →

Related travel pages

Why we regenerated this article: Bottom quartile ↓ 20% ($147 → $117). We only rewrite when the underlying price index actually moves — stable weeks keep the previous take.

AI-authored from this route's 30-day price index. Article last regenerated Oct 10, 2026. Fares shift continuously — confirm at booking.