Boston to San Juan BOS → SJU
Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU)
The cheapest return found recently is $266 with Frontier Airlines, 10 Jan 2027 – 14 Jan 2027, found today.
Return
The cheapest return fare on each of 11 departure dates is usually $367 to $444.
Cheapest return found recently
$266
10 Jan 2027 – 14 Jan 2027 · Frontier Airlines
Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU)
Leaves 11:08 a.m. · Return leaves 10:53 p.m. · 15 h 41 min of travel, both ways together
out nonstop, back 1 stop
found today
Cheapest nonstop return
$499
29 Jan 2027 – 1 Feb 2027 · jetBlue
Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU)
Leaves 5:25 a.m. · Return leaves 6:01 a.m. · 8 h 11 min of travel, both ways together
out nonstop, back nonstop
found 4 days ago
Found recently, and the cheapest we hold
$266 10 Jan 2027 – 14 Jan 2027found todaySee prices for these dates
It is also the cheapest return we hold, of any age.
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest return we saw each day was $264 to $394.
25 days is a short history, so treat this range as an early guide.
Those were the prices on those days, not today's.
Is this a good return price?
Compared with the cheapest return fare on each of 11 departure dates from 4 Nov to 6 Feb 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other 4-night return fares leaving within 3 days of 10 Jan 2027 to compare.
Every date we hold
16 fares on 11 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 4 Nov – 9 Nov | $452 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found 4 days ago | See prices for these dates |
| 6 Nov – 9 Nov | $373 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 2 stops | found 5 days ago | See prices for these dates |
| 11 Nov – 14 Nov | $360 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found 6 days ago | See prices for these dates |
| 8 Jan 2027 – 14 Jan 2027 | $301 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out nonstop, back 1 stop | found 3 days ago | See prices for these dates |
| 10 Jan 2027 – 14 Jan 2027 | $266 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out nonstop, back 1 stop | found today | See prices for these dates |
| 11 Jan 2027 – 14 Jan 2027 | $380 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out nonstop, back 1 stop | found 3 days ago | See prices for these dates |
| 15 Jan 2027 – 18 Jan 2027 | $384 | Frontier Airlines | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found 3 days ago | See prices for these dates |
| 22 Jan 2027 – 26 Jan 2027 | $469 | jetBlue | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out nonstop, back nonstop | found 5 days ago | See prices for these dates |
| 23 Jan 2027 – 26 Jan 2027 | $436 | Allegiant Air | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back nonstop | found 5 days ago | See prices for these dates |
| 29 Jan 2027 – 1 Feb 2027 | $499 | jetBlue | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out nonstop, back nonstop | found 4 days ago | See prices for these dates |
| 6 Feb 2027 – 10 Feb 2027 | $403 | Allegiant Air | Logan International Airport (BOS) → Luis Munoz Marin International Airport (SJU) | out 1 stop, back 1 stop | found 4 days ago | See prices for these dates |
Which month looks cheapest?
January 2027 is the cheapest month — from $266.
Airlines on the cheapest dates: Frontier Airlines, jetBlue, Allegiant Air.
Premium cabin fares from Boston to San Juan
We hold no premium economy, business or first-class fares for this route: we collect them for the busiest routes, and this one is not among them yet.
Today's prices for 10 Jan 2027 – 14 Jan 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Boston to San Juan?
Return
Fares 30 to 59 days before departure were typically 31% lower than 0 to 6 days before departure.
From the cheapest return each day between 24 Sept and 18 Oct (25 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 0–6 days | $483 | $400 | +45% | 13 |
| 7–13 days | $427 | $378 | +28% | 8 |
| 14–29 days | $372 | $328 | +12% | 17 |
| 30–59 days | $333 | $315 | Cheapest seen | 18 |
| 60–89 days | $384 | $275 | +15% | 12 |
| 90–179 days | $345 | $264 | +4% | 25 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
Boston → Saint Thomas
125 km from San Juan
$592
$326 more than flying to San Juan
10 Apr 2027 – 18 Apr 2027 · BOS → STT · out 1 stop, back nonstop
found today
Hartford → San Juan
142 km from Boston
$266
The same price as flying from Boston
3 Dec – 7 Dec · BDL → SJU · out nonstop, back nonstop
found 6 days ago
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
One-way
Hartford → San Juan
142 km from Boston
$193
30 May 2027 · BDL → SJU · 1 stop
found 2 days ago
Cheapest recent price on each route — one way, per traveler in Economy. Distances are in a straight line.
Live price for these dates
The cheapest return found recently is for 10 Jan 2027 – 14 Jan 2027. A live search on this page shows what those dates cost now, for one adult in economy.
Prices are what travelers' searches on Aviasales found in the last 7 days, in US dollars: the price the seller showed on Aviasales; bags may cost extra. Fares change, so check today's price before you book. How our prices work