Las Vegas to Ontario flights in December 2026 from $23 LAS → ONT
McCarran International Airport (LAS) → Ontario International Airport (ONT)
For departures in December 2026, the cheapest return found recently is $43 with Frontier Airlines, 30 Dec – 31 Dec, found 2 days ago. The cheapest one-way found recently is $23 with Frontier Airlines, 31 Dec, found yesterday.
Return
In December 2026, the cheapest return fare on each of 3 departure dates is usually $42 to $45. Across all 8 departure dates we hold on this route, it is usually $43 to $90. Of the 2 months with enough return fares to compare, December 2026 is usually the cheapest.
Cheapest return found recently
$43
30 Dec – 31 Dec · Frontier Airlines
McCarran International Airport (LAS) → Ontario International Airport (ONT)
out nonstop, back nonstop
found 2 days ago
Cheapest we hold, of any age
$42
25 Dec – 1 Jan 2027 · Frontier Airlines
McCarran International Airport (LAS) → Ontario International Airport (ONT)
out nonstop, back nonstop
found 4 days ago
The cheapest dates in December 2026
| Dates | From | Airline | Stops | Found | |
|---|---|---|---|---|---|
| 25 Dec – 1 Jan 2027 | $42 | Frontier Airlines | out nonstop, back nonstop | found 4 days ago | See prices for these dates |
| 30 Dec – 31 Dec | $43 | Frontier Airlines | out nonstop, back nonstop | found 2 days ago | See prices for these dates |
| 4 Dec – 6 Dec | $47 | Frontier Airlines | out nonstop, back nonstop | found 4 days ago | See prices for these dates |
Every date we hold
3 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 4 Dec – 6 Dec | $47 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | out nonstop, back nonstop | found 4 days ago | See prices for these dates |
| 25 Dec – 1 Jan 2027 | $42 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | out nonstop, back nonstop | found 4 days ago | See prices for these dates |
| 30 Dec – 31 Dec | $43 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | out nonstop, back nonstop | found 2 days ago | See prices for these dates |
Which month looks cheapest?
December 2026 is the cheapest month — from $42.
One-way
In December 2026, the cheapest one-way fare on each of 7 departure dates is usually $22 to $29. Across all 22 departure dates we hold on this route, it is usually $29 to $69. Of the 3 months with enough one-way fares to compare, December 2026 is usually the cheapest.
Cheapest one-way found recently
$23
31 Dec · Frontier Airlines
McCarran International Airport (LAS) → Ontario International Airport (ONT)
nonstop
found yesterday
Cheapest we hold, of any age
$18
1 Dec · Frontier Airlines
McCarran International Airport (LAS) → Ontario International Airport (ONT)
nonstop
found 3 days ago
The cheapest dates in December 2026
| Dates | From | Airline | Stops | Found | |
|---|---|---|---|---|---|
| 1 Dec | $18 | Frontier Airlines | nonstop | found 3 days ago | Open this trip |
| 29 Dec | $21 | Frontier Airlines | stops unknown | found 2 days ago | Open this trip |
| 31 Dec | $23 | Frontier Airlines | nonstop | found yesterday | Open this trip |
| 3 Dec | $24 | Frontier Airlines | nonstop | found 2 days ago | Open this trip |
| 4 Dec | $29 | Frontier Airlines | nonstop | found 2 days ago | Open this trip |
Every date we hold
7 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 1 Dec | $18 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | nonstop | found 3 days ago | Open this trip |
| 3 Dec | $24 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | nonstop | found 2 days ago | Open this trip |
| 4 Dec | $29 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | nonstop | found 2 days ago | Open this trip |
| 18 Dec | $29 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | nonstop | found 4 days ago | Open this trip |
| 25 Dec | $29 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | nonstop | found 2 days ago | Open this trip |
| 29 Dec | $21 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | stops unknown | found 2 days ago | Open this trip |
| 31 Dec | $23 | Frontier Airlines | McCarran International Airport (LAS) → Ontario International Airport (ONT) | nonstop | found yesterday | Open this trip |
Which month looks cheapest?
December 2026 is the cheapest month — from $18.
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