Ontario to Washington ONT → DCA, IAD
Ontario International Airport (ONT) → Ronald Reagan National Airport (DCA), Washington Dulles International Airport (IAD)
The cheapest return found recently is $439 with United Airlines, 1 Jan 2027 – 10 Jan 2027, found yesterday. The cheapest one-way found recently is $176 with Frontier Airlines, 4 Jan 2027, found 5 days ago.
Return
The cheapest return fare on each of 4 departure dates is usually $407 to $499.
Cheapest return found recently
$439
1 Jan 2027 – 10 Jan 2027 · United Airlines
Ontario International Airport (ONT) → Washington Dulles International Airport (IAD)
Leaves 4:00 p.m. · Return leaves 6:20 a.m. · 18 h 26 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
$439 1 Jan 2027 – 10 Jan 2027found yesterdaySee prices for these dates
$311 22 Nov – 24 Novfound 3 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 $224 to $257.
At $439, the cheapest return found recently is above that range.
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 22 Nov to 7 Apr 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 9-night return fares leaving within 3 days of 1 Jan 2027 to compare.
Every date we hold
4 fares on 4 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 22 Nov – 24 Nov | $311 | Frontier Airlines | Ontario International Airport (ONT) → Ronald Reagan National Airport (DCA) | out 1 stop, back 1 stop | found 3 days ago | See prices for these dates |
| 28 Dec – 1 Jan 2027 | $516 | United Airlines | Ontario International Airport (ONT) → Washington Dulles International Airport (IAD) | out 1 stop, back nonstop | found today | See prices for these dates |
| 1 Jan 2027 – 10 Jan 2027 | $439 | United Airlines | Ontario International Airport (ONT) → Washington Dulles International Airport (IAD) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
| 7 Apr 2027 – 11 Apr 2027 | $493 | United Airlines | Ontario International Airport (ONT) → Ronald Reagan National Airport (DCA) | out 1 stop, back nonstop | found yesterday | See prices for these dates |
Which month looks cheapest?
November 2026 is the cheapest month — from $311.
Airlines on the cheapest dates: United Airlines, Frontier Airlines.
One-way
Not enough comparable prices yet for a usual one-way price.
Cheapest one-way found recently
$176
4 Jan 2027 · Frontier Airlines
Ontario International Airport (ONT) → Ronald Reagan National Airport (DCA)
Leaves 4:46 p.m. · 26 h 13 min trip
1 stop
found 5 days ago
Cheapest nonstop one-way
None seen yet.
Found recently, and the cheapest we hold
$176 4 Jan 2027found 5 days agoOpen this trip
It is also the cheapest one-way we hold, of any age.
What have prices looked like?
Over 25 days, 24 Sept to 18 Oct, the cheapest one-way we saw each day was $124 to $274.
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 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 4 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 | |
|---|---|---|---|---|---|---|
| 4 Jan 2027 | $176 | Frontier Airlines | Ontario International Airport (ONT) → Ronald Reagan National Airport (DCA) | 1 stop | found 5 days ago | Open this trip |
Airlines on the cheapest dates: Frontier Airlines.
Premium cabin fares from Ontario to Washington
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 1 Jan 2027 – 10 Jan 2027 in another cabin: Premium economy · Business · First
Today's prices for 4 Jan 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Ontario to Washington?
Return
Fares 14 to 29 days before departure were typically 29% 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 | $360 | $224 | +42% | 18 |
| 7–13 days | $307 | $259 | +21% | 14 |
| 14–29 days | $254 | $251 | Cheapest seen | 19 |
| 30–59 days | $257 | $235 | +1% | 25 |
| 60–89 days | $324 | $271 | +28% | 17 |
| 90–179 days | $493 | $476 | +94% | 9 |
| 180+ days | $438 | $432 | +72% | 21 |
One-way
Fares 60 to 89 days before departure were typically 11% lower than 14 to 29 days before departure.
From the cheapest one-way 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 |
|---|---|---|---|---|
| 14–29 days | $144 | $132 | +13% | 8 |
| 60–89 days | $128 | $124 | Cheapest seen | 12 |
| 90–179 days | $247 | $238 | +93% | 9 |
| 180+ days | $221 | $221 | +73% | 14 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
Los Angeles → Washington
56 km from Ontario
$372
$67 less than flying from Ontario
28 Dec – 1 Jan 2027 · LAX → DCA · out 1 stop, back nonstop
found today
Ontario → Baltimore
57 km from Washington
$454
$15 more than flying to Washington
25 Oct – 30 Oct · ONT → BWI · out 1 stop, back 1 stop
found yesterday
Long Beach → Washington
60 km from Ontario
$513
$74 more than flying from Ontario
7 Apr 2027 – 11 Apr 2027 · LGB → DCA · out 1 stop, back nonstop
found yesterday
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
One-way
Los Angeles → Washington
56 km from Ontario
$164
$12 less than flying from Ontario
5 Jan 2027 · LAX → DCA · 1 stop
found 5 days ago
Ontario → Baltimore
57 km from Washington
$222
$46 more than flying to Washington
21 Jan 2027 · ONT → BWI · 1 stop
found 3 days ago
Long Beach → Washington
60 km from Ontario
$340
$164 more than flying from Ontario
5 Jan 2027 · LGB → DCA · 1 stop
found 5 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 1 Jan 2027 – 10 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