Boston → San Juan flights
Fares on BOS–SJU cluster tightly near $121–$124 at the low end, but can spike to $191 — book when you see anything under $130.
Boston–San Juan: median $124, but budget $160 to stay safe
Key takeaways
- Median fare is $124 across 30 daily snapshots of the cheapest available fares.
- The bottom quartile sits between $120 and $121 — an exceptionally narrow band signaling a genuine fare floor.
- The top quartile jumps to $157 or above, meaning roughly one in four days the cheapest fare is meaningfully pricier.
- The 59% spread (from $120 low to $191 high) is wide enough that timing your search matters — don't assume cheap seats are always available.
- A fare at or below $130 represents solid value; anything above $157 is in elevated territory worth waiting out if your dates are flexible.
30-day price trend
See full numbers and stats on the BOS → SJU price history page.
The full picture
The BOS–SJU price landscape is defined by a striking bifurcation: a dense cluster of very low fares near the floor, and a long tail that can run 50–60% higher. With a median of $124 and a 25th percentile of $121, the data suggest that genuinely cheap inventory does appear with regularity — but the $157 p75 and $191 ceiling are reminders that those seats don't last, and that demand surges (think holiday weekends, school breaks, or major San Juan events) can push the market well above the comfortable zone. The practical message is simple: if you can see a fare at $130 or below, that is historically close to the floor, and waiting for something better carries real risk.
On booking horizon, the 59% spread across 30 daily snapshots implies meaningful volatility in how far out fares were captured. Typically on Caribbean leisure routes like this one, fares soften in the 3–6 week window before departure as carriers manage unsold inventory, then firm up again in the final 10 days. Nothing in this dataset contradicts that general pattern, though it cannot confirm it precisely. What the tight p25 band does suggest is that low fares surface repeatedly — this is not a route where rock-bottom pricing is a one-day anomaly.
No dominant carrier is identifiable from this data, so no airline-specific booking strategy is warranted. The honest caveat: 30 snapshots reflect cached cheapest fares at the moment each snapshot was taken, not a full picture of every departure date or booking lead time. Seasonal demand for San Juan — especially from October through April — can shift this entire distribution upward, so travelers planning winter or spring break travel should treat the $124 median as a best-case baseline rather than a reliable expectation.
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AI-authored from this route's 30-day price index. Article last regenerated Jun 20, 2026. Fares shift continuously — confirm at booking.