Cheap flights from Ontario to Boston from $240 ONT → BOS
Ontario International Airport (ONT) → Logan International Airport (BOS)
The cheapest return found recently is $360 with Southwest Airlines, 12 Dec – 16 Dec, found yesterday. The cheapest one-way found recently is $240 with Southwest Airlines, 27 Feb 2027, found 4 days ago.
- Cheapest one-way found recently
- $240, found 4 days ago
- Cheapest return found recently
- $360, 12 Dec to 16 Dec
- Usual return price
- $507 to $537
- Cheapest month to fly
- December 2026, return fares from $360 found in the last 7 days
Return
The cheapest return fare on each of 6 departure dates is usually $507 to $537.
Cheapest return found recently
$360
12 Dec – 16 Dec · Southwest Airlines
Ontario International Airport (ONT) → Logan International Airport (BOS)
Leaves 6:10 a.m. · Return leaves 3:59 p.m. · 19 h 32 min of travel, both ways together
out 1 stop, back 1 stop
found yesterday
Cheapest nonstop return
None seen yet.
Found recently, and the cheapest we hold
$360 12 Dec – 16 Decfound yesterdaySee prices for these dates
It is also the cheapest return we hold, of any age.
What have prices looked like?
Over 50 days, 24 Sept to 12 Nov, the cheapest return we saw each day was $247 to $417.
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 6 departure dates from 19 Nov to 28 Dec, 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 12 Dec to compare.
Every date we hold
9 fares on 6 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 19 Nov – 22 Nov | $505 | Alaska Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | out 1 stop, back 1 stop | found 5 days ago | See prices for these dates |
| 21 Nov – 30 Nov | $547 | Alaska Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | out 1 stop, back 2 stops | found 5 days ago | See prices for these dates |
| 12 Dec – 16 Dec | $360 | Southwest Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 17 Dec – 3 Jan 2027 | $511 | Southwest Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | out 1 stop, back 1 stop | found 4 days ago | See prices for these dates |
| 20 Dec – 2 Jan 2027 | $538 | Southwest Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | out 2 stops, back 1 stop | found 3 days ago | See prices for these dates |
| 28 Dec – 3 Jan 2027 | $533 | Southwest Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | out 1 stop, back 1 stop | found 3 days ago | See prices for these dates |
Which month looks cheapest?
December 2026 is the cheapest month — from $360.
Airlines on the cheapest dates: Southwest Airlines, Alaska Airlines.
One-way
Not enough comparable prices yet for a usual one-way price.
Cheapest one-way found recently
$240
27 Feb 2027 · Southwest Airlines
Ontario International Airport (ONT) → Logan International Airport (BOS)
Leaves 6:05 a.m. · 7 h 20 min trip
1 stop
found 4 days ago
Cheapest nonstop one-way
None seen yet.
Found recently, and the cheapest we hold
$240 27 Feb 2027found 4 days agoOpen this trip
It is also the cheapest one-way we hold, of any age.
What have prices looked like?
Over 40 days, 24 Sept to 12 Nov, the cheapest one-way we saw each day was $131 to $287.
Those were the prices on those days, not today's.
Is this a good one-way price?
Not enough comparable prices yet: we hold one-way fares on 1 departure date and need at least 3 to say what is usual.
Could nearby dates be cheaper?
We hold no other one-way fares leaving within 3 days of 27 Feb 2027 to compare.
Every date we hold
1 fares on 1 departure dates
See every date as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 27 Feb 2027 | $240 | Southwest Airlines | Ontario International Airport (ONT) → Logan International Airport (BOS) | 1 stop | found 4 days ago | Open this trip |
Airlines on the cheapest dates: Southwest Airlines.
Premium cabin fares from Ontario to Boston
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 12 Dec – 16 Dec in another cabin: Premium economy · Business · First
Today's prices for 27 Feb 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Ontario to Boston?
Return
Fares 14 to 29 days before departure were typically 32% lower than 0 to 6 days before departure.
From the cheapest return each day between 24 Sept and 12 Nov (50 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 | $491 | $310 | +47% | 9 |
| 7–13 days | $480 | $310 | +44% | 25 |
| 14–29 days | $333 | $247 | Cheapest seen | 15 |
| 30–59 days | $352 | $247 | +6% | 44 |
| 60–89 days | $456 | $403 | +37% | 20 |
| 90–179 days | $415 | $368 | +25% | 19 |
| 180+ days | $406 | $368 | +22% | 26 |
One-way
Fares 60 to 89 days before departure were typically 9% lower than 30 to 59 days before departure.
From the cheapest one-way each day between 24 Sept and 12 Nov (40 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 |
|---|---|---|---|---|
| 30–59 days | $209 | $184 | +9% | 10 |
| 60–89 days | $191 | $191 | Cheapest seen | 10 |
| 90–179 days | $240 | $201 | +26% | 21 |
| 180+ days | $211 | $201 | +11% | 17 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
Los Angeles → Boston
56 km from Ontario
$282
$78 less than flying from Ontario
12 Dec – 16 Dec · LAX → BOS · out nonstop, back nonstop
found yesterday
Long Beach → Boston
60 km from Ontario
$458
$98 more than flying from Ontario
12 Dec – 16 Dec · LGB → BOS · out 1 stop, back 1 stop
found yesterday
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
One-way
Los Angeles → Boston
56 km from Ontario
$134
$106 less than flying from Ontario
26 Nov · LAX → BOS · stops unknown
found today
Long Beach → Boston
60 km from Ontario
$222
$18 less than flying from Ontario
27 Feb 2027 · LGB → BOS · 1 stop
found 4 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 12 Dec – 16 Dec. A live search on this page shows what those dates cost now, for one adult in economy.
Questions about this trip
How much is a return flight from Ontario to Boston?
The cheapest return found recently is $360 with Southwest Airlines, 12 Dec to 16 Dec, found yesterday. The cheapest return fare on each of 6 departure dates is usually $507 to $537.
How much is a one-way flight from Ontario to Boston?
The cheapest one-way found recently is $240 with Southwest Airlines, 27 Feb 2027, found 4 days ago.
What is the cheapest month to fly from Ontario to Boston?
December 2026 is the cheapest month for a return, from $360, 12 Dec to 16 Dec, found yesterday.
How far ahead should I book a flight from Ontario to Boston?
In 50 days of prices between 24 Sept and 12 Nov, return fares 14 to 29 days before departure were typically 32% lower than 0 to 6 days before departure. In 40 days of prices between 24 Sept and 12 Nov, one-way fares 60 to 89 days before departure were typically 9% lower than 30 to 59 days before departure.
How long is the flight from Ontario to Boston?
The cheapest one-way found recently, with Southwest Airlines on 27 Feb 2027, takes 7 h 20 min with 1 stop.
Which airlines have the cheapest flights from Ontario to Boston?
Between 19 Nov and 28 Dec, Southwest Airlines has the cheapest return on 4 of the 6 departure dates we hold, and Alaska Airlines on 2.
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