Exceptional1 stop · 17.5h
BOS to BKKThailand
Bangkok
$506
usually $1,140
−56%
Most monthly lows $915–$1,187. Cheaper than every other month on record (5).
- Travel dates
- 7 Mar '27 – 17 Apr '27 · 41 nights
- Airline
Turkish Airlines· $18 per 1,000 km
Flights · BOS → SJU
Boston to San Juan
Best fare, round trip
$242
−33%
below its usual $360
you keep $118
GreatFound
- Depart
- Sat 20 Feb
- Return
- Sat 27 Feb
- Stay
- 7 nights
- Flight
- Nonstop · 4h
- Airline
Frontier Airlines
Most of this route’s monthly lows fall between $275 and $414. The drop beats 82% of measured fares on the board, over 5 observed months.
Cached fare — the booking search re-prices live before you pay.
Puerto RicoSan JuanFive centuries of old town on a Caribbean island that takes US dollars and needs no passport from the States.Best windowDec–AprAirportsLuis Muñoz Marín (SJU)Every route into San JuanFare seasonality
When this route gets cheap.
Fares bottom out in February around $242 and peak in December near $540, 123% dearer, across the 5 months we track. The cheapest itinerary we are tracking flies Frontier Airlines nonstop and takes about 4 hours outbound, on a 7-night trip. At $242 for 2,698 km each way, that works out to about $45 per 1,000 km flown. That is about the $43 per 1,000 km typical of medium-haul fares here. Across the 6 departure cities we track at a similar distance from San Juan, this fare ranks 4th — 49% above the $162 from Chicago. It is also the 2nd cheapest of the 7 routes of similar length we watch out of Boston. The best time to be in San Juan: Dec–Apr.
Day-level prices for the next 4 months
Press a day to compare its fares
The median cached fare across this calendar is 60% higher than when tracking began on 8 Aug — $292 then versus $466 now, across 17 recorded snapshots. This is a calendar-level trend, so an individual deal above can be lower. The lowest single day we have seen here is $200, on 24 Sep.
Cached day-level data for this route is sparse — 10 of 111 days priced, from 52 tracked fares. The days below are shown as found, with no cheapest-day or below-median call.
October 2026
November 2026
December 2026
12345678910111213141516171819202122232425Saturday 26 December: $830. Compare fares from this day.2728293031
January 2027
123Monday 4 January: $402. Compare fares from this day.567891011121314151617181920Thursday 21 January: $432. Compare fares from this day.22232425262728293031
Cached fares · checked 13 Oct 2026
Cheapest in Feb, around $242
33% below the $360 typical fare
$414Oct, above the usual price. Compare October fares.$360Nov, around the usual price. Compare November fares.$540Dec, above the usual price. Compare December fares.$275Jan ’27, below the usual price. Compare January fares.$242Feb, the cheapest month. Compare February fares.
CheapestBelow usualUsualAbove usualPress a month to compare its fares
Cheapest round-trip fare found each month, Boston to San Juan, from cached prices.
Route facts
- Airports
- Logan (BOS) ↔ Luis Muñoz Marín (SJU)
- Flight time
- ≈4 hours outbound
- Distance
- ≈2,698 km each way
- Typical price
- $360 round-trip (seasonal median)
- Airlines on the board
- Frontier Airlines
- Itineraries
- Nonstop available
- Best months to visit
- Dec–Apr
Good to know
BOS → SJU, answered.
Is $242 a good price for Boston to San Juan?
Yes — the seasonal median for this route is around $360 round-trip. At $242 you're 33% below that, which we rate great for this route.
What is the cheapest month to fly from Boston to San Juan?
Across 5 months of cached-fare history, Feb comes out cheapest on this route. The best months to actually be in San Juan are Dec–Apr — when those overlap, that's your window.
How far in advance should I book BOS → San Juan?
We do not publish a number for this, because we cannot measure it yet. Answering it honestly means watching the same departure date on this route over many weeks as it approaches, and that archive is still filling up — so any "book N days ahead" figure here would be borrowed from somewhere else rather than measured. What we can measure is which month is cheap: across 5 months of cached fares, Feb comes out lowest on this route. Our guide Why flight prices change covers what does move a fare.
Are there nonstop flights from Boston to San Juan?
Yes — the current board includes nonstop fares (Frontier Airlines). The outbound leg runs around 4 hours.
Are these prices guaranteed?
No — these are cached fares found on real searches (this one on 17 October). Airlines reprice constantly, so the booking search re-checks the live price before you pay. Fresher finds are far more likely to still be available.
Next step
Sleeping in San Juan?
Lock the flight first — then compare stays for 20–27 Feb '27 · 7 nights.
Browse hotelsMissed it?
Cached fares expire. This route has a feed of its own — follow it and the next BOS → SJU drop reaches you as soon as we find it.
Follow this route’s feedKeep browsing
Related routes on the board.
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$910
usually $1,730
−47%
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$162
usually $340
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Most monthly lows $287–$340. Cheaper than every other month on record (3).
Rare1 stop · 9h
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$223
usually $380
−41%
Most monthly lows $327–$380. Cheaper than every other month on record (3).