Your next trip, last seen at €98
Lowest observedFrontier Airlines · 1 stop · One wayWhen to fly
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The lowest fare we observed for each month. Open a month to see its days, then pick your outbound and return. A day with no price is one we will search for you.
- Lowest observed
- €98, departing 8 Dec 2026 (Last checked: 8 Oct 2026)One-way fare · Priced departure days checked in the last 14 days: 62Check live prices for this route
- Airlines seen
- Alaska Airlines, Allegiant Air, American Airlines, Delta Air Lines, Frontier Airlines, United Airlines
- Typical journey time
- 8h 01m
About this route
Explore the fares we observed from Billings to San Diego. Prices move often, so pick your dates to see the latest options.
- Route distance
- 1,631 km
- Typical journey time
- 8h 01m
- Airlines seen
- Alaska Airlines, Allegiant Air, American Airlines, Delta Air Lines, Frontier Airlines, United Airlines
- Seen on fares with a connection
- Alaska Airlines, Allegiant Air, United Airlines, Frontier Airlines, American Airlines, Delta Air Lines
- Alternative airports
- CLD
Route-level information; individual journeys vary.
We have not observed non-stop service on this route; the fares shown include at least one stop.
A clearer picture of your fare
Airport to city: straight-line distance
- Billings Logan International Airport (BIL) → Billings, city gazetteer reference point (45.7833, -108.5007): ≈ 4 km.
- San Diego International Airport (SAN) → San Diego, city gazetteer reference point (32.7153, -117.1573): ≈ 4 km.
- McClellan-Palomar Airport (CLD) → San Diego, city gazetteer reference point (32.7153, -117.1573): ≈ 47 km.
Approximate distances calculated from coordinates, not road distances or travel times. These airports serve the city; they are not confirmed endpoints of an offer.
Lowest fare by departure month
Cheapest month from Billings to San Diego: December 2026, from €98 (checked 8 Oct 2026).
| Month | Lowest fare | Priced days |
|---|---|---|
| October 2026 | €130 | 19 |
| November 2026 | €122 | 4 |
| December 2026 | €98 | 31 |
| January 2027 | €98 | 8 |
Lowest fare by day of the week
Cheapest day of the week from Billings to San Diego: Monday, from €98 (checked 8 Oct 2026).
| Day | Lowest fare | Priced days |
|---|---|---|
| Monday | €98 | 9 |
| Tuesday | €98 | 10 |
| Wednesday | €175 | 9 |
| Thursday | €162 | 9 |
| Friday | €126 | 9 |
| Saturday | €152 | 8 |
| Sunday | €109 | 8 |
One-way fares checked in the last 14 days. Each figure is the lowest priced departure day we saw, not a guaranteed fare.
Lowest fare by days before departure
Lowest fare from Billings to San Diego by days until departure (31 to 60 days): €98 (checked 8 Oct 2026).
| Days before departure | Lowest fare | Priced days |
|---|---|---|
| 0 to 7 days | €199 | 8 |
| 8 to 30 days | €130 | 14 |
| 31 to 60 days | €98 | 13 |
| 61 days or more | €98 | 27 |
One-way fares checked in the last 14 days. Each figure is the lowest stored fare for that distance to departure, not a price forecast.
Fares for different departure dates, checked now; not a guide to when to book.
Lowest one-way fare we saw per airline
Cheapest airline from Billings to San Diego: Allegiant Air, from €98 (checked 8 Oct 2026).
| Airline | Lowest fare | Priced days |
|---|---|---|
| Allegiant Air | €98Dec 14, 2026 | 24 |
| Frontier Airlines | €98Dec 8, 2026 | 3 |
| Alaska Airlines | €174Oct 26, 2026 | 21 |
| United Airlines | €174Oct 26, 2026 | 18 |
One-way fares checked in the last 14 days. An airline listed here had a fare on at least 3 departure days. Each figure is the lowest we saw, not a guaranteed fare. Connecting itineraries are included; the date is the departure day of that fare.
Frequently asked
How much is a flight from Billings to San Diego?
The lowest fare we have observed is €98, found on 8 Oct 2026. Prices move, so read it as a floor rather than a quote.
When is the cheapest month to fly from Billings to San Diego?
Cheapest month from Billings to San Diego: December 2026, from €98 (checked 8 Oct 2026).
Are there direct flights from Billings to San Diego?
Our data holds no non-stop flight from Billings to San Diego. The fares on this page include at least one stop.
Which airlines fly from Billings to San Diego?
These are the carriers we have seen on the route: Alaska Airlines, Allegiant Air, American Airlines, Delta Air Lines, Frontier Airlines, United Airlines.
How long does the flight from Billings to San Diego take?
The average journey time across the 78 fares we observed is 15h 22m, including any stops. Individual departures vary; the fastest observed flight is listed in the route facts above.
How many of the observed Billings to San Diego fares were non-stop?
None of the 78 fares we observed was non-stop; every one included at least one stop. That describes our observations, not every flight that operates.
Which day of the week is cheapest from Billings to San Diego?
Cheapest day of the week from Billings to San Diego: Monday, from €98 (checked 8 Oct 2026).
Which airline has the lowest fare from Billings to San Diego?
Cheapest airline from Billings to San Diego: Allegiant Air, from €98 (checked 8 Oct 2026).
How observed prices work, what "No data" means and what a fare includes: Read the flight price guide
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Recently observed fares. Prices may change.
Last checked: 8 Oct 2026