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 → LIS
Boston to Lisbon
Best fare, round trip
$490
−30%
below its usual $705
you keep $215
GreatFound
- Depart
- Fri 15 Jan
- Return
- Mon 18 Jan
- Stay
- 3 nights
- Flight
- 1 stop · 9h
- Airline
Aer Lingus
Most of this route’s monthly lows fall between $552 and $856. The drop beats 78% of measured fares on the board, over 6 observed months.
Cached fare — the booking search re-prices live before you pay.
PortugalLisbonTiled hills, custard tarts, Atlantic light — TAP’s hub wars keep this Europe’s cheapest gateway.Best windowMar–Jun · Sep–OctAirportsHumberto Delgado (LIS)Every route into LisbonFare seasonality
When this route gets cheap.
Fares bottom out in January around $365 and peak in December near $859, 135% dearer, across the 6 months we track. The cheapest itinerary we are tracking makes one stop and takes about 9 hours outbound, on a 3-night trip — ticketed under Aer Lingus, which on a connecting fare need not operate every leg. At $490 for 5,131 km each way, that works out to about $48 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 Lisbon, this fare ranks 3rd — 27% above the $386 from Toronto. It is also the 3rd cheapest of the 19 routes of similar length we watch out of Boston. The best time to be in Lisbon: Mar–Jun · Sep–Oct.
The 7 days we hold a cached fare for
Press a date to compare its fares
The median cached fare across this calendar is 25% lower than when tracking began on 8 Aug — $746 then versus $563 now, across 19 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 $365, on 15 Jan '27.
- Sun 18 Oct$552
- Wed 21 Oct$563
- Thu 22 Oct$563
- Tue 17 Nov$622
- Sat 21 Nov$926
- Tue 22 Dec$859
- Fri 15 Jan$365lowest
These are the only days we have a cached price for on this route so far — not the only days it flies. The search above covers any date.
Cached fares · checked 15 Oct 2026
Cheapest in Jan, around $365
48% below the $705 typical fare
$552Oct, below the usual price. Compare October fares.$622Nov, below the usual price. Compare November fares.$859Dec, above the usual price. Compare December fares.$365Jan ’27, the cheapest month. Compare January fares.$704Feb, around the usual price. Compare February fares.$856Jun, above the usual price. Compare June fares.
CheapestBelow usualUsualAbove usualPress a month to compare its fares
Cheapest round-trip fare found each month, Boston to Lisbon, from cached prices.
Route facts
- Airports
- Logan (BOS) ↔ Humberto Delgado (LIS)
- Flight time
- ≈9 hours outbound
- Distance
- ≈5,131 km each way
- Typical price
- $705 round-trip (seasonal median)
- Airlines on the board
- Aer Lingus
- Itineraries
- Connections on current fares
- Best months to visit
- Mar–Jun · Sep–Oct
Good to know
BOS → LIS, answered.
Is $490 a good price for Boston to Lisbon?
Yes — the seasonal median for this route is around $705 round-trip. At $490 you're 30% below that, which we rate great for this route.
What is the cheapest month to fly from Boston to Lisbon?
Across 6 months of cached-fare history, Jan comes out cheapest on this route. The best months to actually be in Lisbon are Mar–Jun · Sep–Oct — when those overlap, that's your window.
How far in advance should I book BOS → Lisbon?
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 6 months of cached fares, Jan 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 Lisbon?
The current cheapest fares involve a connection, ticketed under Aer Lingus. We hold no nonstop fare on this route right now, which does not mean none flies — search your exact dates to see what does.
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 Lisbon?
Lock the flight first — then compare stays for 15–18 Jan '27 · 3 nights.
Browse hotelsMissed it?
Cached fares expire. This route has a feed of its own — follow it and the next BOS → LIS drop reaches you as soon as we find it.
Follow this route’s feedKeep browsing
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