Ontario to Baltimore ONT → BWI
Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI)
The cheapest return found recently is $454 with Frontier Airlines, 25 Oct – 30 Oct, found yesterday. The cheapest one-way found recently is $222 with Frontier Airlines, 21 Jan 2027, found 3 days ago.
Return
The cheapest return fare on each of 4 departure dates is usually $290 to $447.
Cheapest return found recently
$454
25 Oct – 30 Oct · Frontier Airlines
Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI)
Leaves 8:03 p.m. · Return leaves 2:07 p.m. · 19 h 56 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
$454 25 Oct – 30 Octfound yesterdaySee prices for these dates
$267 6 Nov – 9 Novfound 5 days agoSee prices for these dates
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest return we saw each day was $185 to $467.
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 4 departure dates from 23 Oct to 4 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 5-night return fares leaving within 3 days of 25 Oct to compare.
Every date we hold
4 fares on 4 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 23 Oct – 1 Nov | $445 | Frontier Airlines | Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI) | out 1 stop, back 1 stop | found 6 days ago | See prices for these dates |
| 25 Oct – 30 Oct | $454 | Frontier Airlines | Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 6 Nov – 9 Nov | $267 | Frontier Airlines | Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI) | out 1 stop, back 1 stop | found 5 days ago | See prices for these dates |
| 4 Dec – 7 Dec | $298 | Frontier Airlines | Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI) | out 3 stops, back 1 stop | found 5 days ago | See prices for these dates |
Which month looks cheapest?
November 2026 is the cheapest month — from $267.
Airlines on the cheapest dates: Frontier Airlines.
One-way
Not enough comparable prices yet for a usual one-way price.
Cheapest one-way found recently
$222
21 Jan 2027 · Frontier Airlines
Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI)
Leaves 7:10 p.m. · 11 h 11 min trip
1 stop
found 3 days ago
Cheapest nonstop one-way
None seen yet.
Found recently, and the cheapest we hold
$222 21 Jan 2027found 3 days agoOpen this trip
It is also the cheapest one-way we hold, of any age.
What have prices looked like?
Over 11 days, 27 Sept to 18 Oct, the cheapest one-way we saw each day was $210 to $222.
At $222, the cheapest one-way found recently is at the high end of that range.
11 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 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 21 Jan 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 | |
|---|---|---|---|---|---|---|
| 21 Jan 2027 | $222 | Frontier Airlines | Ontario International Airport (ONT) → Baltimore/Wash International Thurgood Marshall Airport (BWI) | 1 stop | found 3 days ago | Open this trip |
Airlines on the cheapest dates: Frontier Airlines.
Premium cabin fares from Ontario to Baltimore
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 25 Oct – 30 Oct in another cabin: Premium economy · Business · First
Today's prices for 21 Jan 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Ontario to Baltimore?
Return
Fares 30 to 59 days before departure were typically 32% 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 | $435 | $320 | +46% | 17 |
| 7–13 days | $445 | $349 | +49% | 11 |
| 14–29 days | $299 | $249 | +0% | 10 |
| 30–59 days | $298 | $249 | Cheapest seen | 7 |
| 60–89 days | $467 | $467 | +57% | 8 |
One-way
Not enough history yet: in 11 days of one-way prices, 27 Sept to 18 Oct, fewer than 3 booking ranges had prices on 7 days or more.
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
Ontario → Washington
57 km from Baltimore
$439
$15 less than flying to Baltimore
1 Jan 2027 – 10 Jan 2027 · ONT → IAD · out 1 stop, back 1 stop
found yesterday
Long Beach → Baltimore
60 km from Ontario
$481
$27 more than flying from Ontario
1 Jan 2027 – 10 Jan 2027 · LGB → BWI · out 1 stop, back nonstop
found yesterday
Los Angeles → Baltimore
56 km from Ontario
$484
$30 more than flying from Ontario
25 Oct – 30 Oct · LAX → BWI · out 1 stop, back 1 stop
found yesterday
Ontario → Philadelphia
145 km from Baltimore
$604
$150 more than flying to Baltimore
30 Oct – 2 Nov · ONT → PHL · out 2 stops, 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 → Baltimore
56 km from Ontario
$158
$64 less than flying from Ontario
21 Jan 2027 · LAX → BWI · nonstop
found 3 days ago
Ontario → Washington
57 km from Baltimore
$176
$46 less than flying to Baltimore
4 Jan 2027 · ONT → DCA · 1 stop
found 5 days ago
Long Beach → Baltimore
60 km from Ontario
$218
$4 less than flying from Ontario
21 Jan 2027 · LGB → BWI · 1 stop
found 3 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 25 Oct – 30 Oct. 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