Ontario to Las Vegas flights in December 2026 from $21 ONT → LAS
Ontario International Airport (ONT) → McCarran International Airport (LAS)
For departures in December 2026, the cheapest return found recently is $33 with Frontier Airlines, 5 Dec – 9 Dec, found 3 days ago. The cheapest one-way found recently is $21 with Frontier Airlines, 29 Dec, found 2 days ago.
Return
In December 2026, the cheapest return fare on each of 10 departure dates is usually $44 to $51. Across all 27 departure dates we hold on this route, it is usually $46 to $140. Of the 3 months with enough return fares to compare, 1 is usually cheaper than December 2026.
Cheapest return found recently
$33
5 Dec – 9 Dec · Frontier Airlines
Ontario International Airport (ONT) → McCarran International Airport (LAS)
out nonstop, back nonstop
found 3 days ago
It is also the cheapest return we hold, of any age.
The cheapest dates in December 2026
| Dates | From | Airline | Stops | Found | |
|---|---|---|---|---|---|
| 5 Dec – 9 Dec | $33 | Frontier Airlines | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 15 Dec – 22 Dec | $33 | Frontier Airlines | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 23 Dec – 25 Dec | $43 | Frontier Airlines | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 6 Dec – 8 Dec | $46 | Frontier Airlines | out nonstop, back nonstop | found 5 days ago | See prices for these dates |
| 7 Dec – 8 Dec | $46 | Frontier Airlines | out nonstop, back nonstop | found 5 days ago | See prices for these dates |
Every date we hold
10 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 4 Dec – 6 Dec | $97 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 7 days ago | See prices for these dates |
| 5 Dec – 9 Dec | $33 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 6 Dec – 8 Dec | $46 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 5 days ago | See prices for these dates |
| 7 Dec – 8 Dec | $46 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 5 days ago | See prices for these dates |
| 14 Dec – 17 Dec | $47 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 6 days ago | See prices for these dates |
| 15 Dec – 22 Dec | $33 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 18 Dec – 22 Dec | $50 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 7 days ago | See prices for these dates |
| 23 Dec – 25 Dec | $43 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 25 Dec – 1 Jan 2027 | $51 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 3 days ago | See prices for these dates |
| 30 Dec – 1 Jan 2027 | $53 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | out nonstop, back nonstop | found 4 days ago | See prices for these dates |
Which month looks cheapest?
December 2026 is the cheapest month — from $33.
One-way
In December 2026, the cheapest one-way fare on each of 13 departure dates is usually $21 to $29. Across all 34 departure dates we hold on this route, it is usually $23 to $118. Of the 3 months with enough one-way fares to compare, 1 is usually cheaper than December 2026.
Cheapest one-way found recently
$21
29 Dec · Frontier Airlines
Ontario International Airport (ONT) → McCarran International Airport (LAS)
nonstop
found 2 days ago
Cheapest we hold, of any age
$20
2 Dec · Frontier Airlines
Ontario International Airport (ONT) → McCarran International Airport (LAS)
nonstop
found 7 days ago
The cheapest dates in December 2026
| Dates | From | Airline | Stops | Found | |
|---|---|---|---|---|---|
| 2 Dec | $20 | Frontier Airlines | nonstop | found 7 days ago | Open this trip |
| 5 Dec | $20 | Frontier Airlines | nonstop | found 6 days ago | Open this trip |
| 8 Dec | $21 | Frontier Airlines | nonstop | found 3 days ago | Open this trip |
| 29 Dec | $21 | Frontier Airlines | nonstop | found 2 days ago | Open this trip |
| 30 Dec | $21 | Frontier Airlines | nonstop | found 2 days ago | Open this trip |
Every date we hold
13 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 1 Dec | $56 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 3 days ago | Open this trip |
| 2 Dec | $20 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 7 days ago | Open this trip |
| 3 Dec | $25 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 2 days ago | Open this trip |
| 5 Dec | $20 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 6 days ago | Open this trip |
| 6 Dec | $29 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 7 days ago | Open this trip |
| 8 Dec | $21 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 3 days ago | Open this trip |
| 9 Dec | $22 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 6 days ago | Open this trip |
| 20 Dec | $29 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 2 days ago | Open this trip |
| 25 Dec | $23 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 3 days ago | Open this trip |
| 28 Dec | $136 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 2 days ago | Open this trip |
| 29 Dec | $21 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 2 days ago | Open this trip |
| 30 Dec | $21 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 2 days ago | Open this trip |
| 31 Dec | $24 | Frontier Airlines | Ontario International Airport (ONT) → McCarran International Airport (LAS) | nonstop | found 2 days ago | Open this trip |
Which month looks cheapest?
December 2026 is the cheapest month — from $20.
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