Flights Denver → Ontario
As of November 2026, economy flights from Denver to Ontario have a typical range USD 525–697, median USD 638. Full range across all 588 offers: USD 293–2496. We analyzed 588 offers from 8 airlines in a single price check.
Preview snapshot — prices change. Search for live results.
Data collected by LetsFG's multi-source price checks — every airline and the major booking sites checked for this route. How we collect data →
Best offers by airline: Denver → Ontario
Based on 588 offers · November 2026. Prices and availability change — run a live search to confirm.
Bag & seat fees: Denver → Ontario
Add-on pricing from the cheapest available offer per airline · November 2026 · USD
| Airline | Carry-on | Checked bag | Seat selection |
|---|---|---|---|
| Frontier Airlines | — | — | — |
| United | — | — | — |
| American Airlines | — | — | — |
| Southwest Airlines | — | — | — |
| Alaska Airlines | — | — | — |
| Delta | — | — | — |
Fees are estimates from the prices we checked and may not reflect your specific itinerary, booking class, or payment method. Run a live search for exact pricing.
How much do flights from Denver to Ontario cost?
Based on 588 offers · November 2026
Denver to Ontario flights ranged from USD 293 to USD 2496 across 588 offers analyzed in November 2026. The chart below shows how prices distributed across all 588 offers.
These 588 offers (November 2026) span multiple departure dates and booking windows — your travel dates may fall anywhere in this distribution. Only a live search shows where your specific trip lands.
50% of offers priced between USD 597 and USD 656
What hidden fees do Denver to Ontario flights charge?
Ancillary fees — bags, seat selection, and payment surcharges — can add 10–25% to the base fare on Denver to Ontario routes. The breakdown below is based on 588 offers analyzed in November 2026.
| Carrier | Avg fee (USD) | % of base fare |
|---|---|---|
| F9 | 10 | 2% |
| UA | 10 | 2% |
| AA | 10 | 2% |
| WN | 0 | 0% |
| AS | 10 | 1% |
| DL | 10 | 1% |
Frontier Airlines: base ~USD 364 + fees USD 10 = ~USD 374 total. United Airlines: base ~USD 524 + fees USD 10 = ~USD 534 total.
Total costs diverge further when fees are added on this route. Always compare total cost, not just the advertised base fare.
Estimates based on median total minus average ancillary fee. Actual base fares vary by itinerary.Fee levels vary significantly across carriers on this route — some carriers charge 50%+ above the base fare in ancillary fees.
Run your search to see itemized fees for your itineraryWhich airline is cheapest from Denver to Ontario?
8 airlines flew Denver to Ontario in this dataset. Knowing the airline isn't enough — the typical fare range below shows how far prices swing on each one. Median and range include all fees we recorded.
Even on the cheapest airline (Frontier), fares ranged USD 294–312 in this snapshot. Your exact price depends on your dates and how far ahead you book — run a live search to see your number →
| Airline | Offers | Typical range (USD) | Median (USD) | Fees (USD) |
|---|---|---|---|---|
 Frontier | 9 | 294–312 | 294 | n/a |
 AA|F9 | 1 | — | 309 | n/a |
 Frontier Airlines | 39 | 306–615 | 374 | 10 (3%) |
 United Airlines | 28 | 455–750 | 534 | 10 (2%) |
 American Airlines | 32 | 473–676 | 550 | 10 (2%) |
 Southwest Airlines | 460 | 589–681 | 638 | 0 (0%) |
 Alaska Airlines | 14 | 627–792 | 718 | 10 (1%) |
 Delta Air Lines | 5 | 828–1953 | 918 | 10 (1%) |
Where do the best Denver → Ontario prices come from?
We checked direct airlines, travel agencies, and meta-search for this route. On this route the lowest median came from travel agency sources, but the cheapest channel shifts by route and date — which is exactly why a live search across all of them wins.
We compare every airline and the major booking sites but never disclose which — that's our edge. Prices are the ones we observed and aren't official data from any platform. Run a live search and we bring you the cheapest, wherever it is.
Key facts: Denver to Ontario flights
- Full-service carriers on Denver–Ontario cost 1.4x more than budget airlines (USD 606 vs USD 435 median; overall median USD 638).
- F9 charges 1.0x more in ancillary fees than DL — USD 10 vs USD 10 avg per booking.
- The same route priced USD 344 apart depending on where it was booked — the lowest median was USD 294. We search every airline and the major booking sites at once so you always see that lowest price.
Frequently asked questions
- How much does a flight from Denver to Ontario cost?
- Based on 588 offers analyzed, Denver to Ontario flights range from USD 293 to USD 2496, with a median price of USD 638. Search for your specific dates →
- What hidden fees should I expect on Denver to Ontario flights?
- On average, ancillary fees (bags, seat selection) add USD 2 to the base fare on Denver to Ontario flights. See itemized fees for your itinerary →
- Which airline is cheapest on Denver to Ontario including all fees?
- Frontier has the lowest median fare on Denver to Ontario at USD 294 (median across 9 offers in our snapshot). Check which airline wins on your dates →
- Which booking site has the cheapest Denver–Ontario flights?
- It depends on your dates — no single site is always cheapest. We search every airline and the major booking sites at once (travel agencies and meta-search included) and surface whichever is lowest; the best median in this snapshot was USD 294. Run a live search and we'll find the cheapest for you →
- Why do prices vary so much on Denver to Ontario routes?
- Denver to Ontario has 8 airlines competing, creating a price range from USD 293 to USD 2496 across 588 offers. Prices on this route change with booking timing, advance purchase, and ancillary add-ons. Find where your trip lands in the distribution →
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