Flights from Denver to Ontario
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From $190 · Prices update daily
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The quick answer
Flights from Denver to Ontario start around $190 round-trip. Main carrier: Frontier Airlines (direct flights available). Cheapest month: July; peak: August (about +22%).
Price calendar — next 60 days
★ Cheapest: $190 on Fri, Aug 21 · Direct · F9
Lowest return fares · Prices update daily · Final price confirmed at booking
Price calendar — Denver to Ontario
Month-by-month lowest fares. Green = cheapest dates.
United States essentials
🇺🇸 Domestic flight — no passport required
Domestic flight — no passport required for US citizens. Bring REAL ID for security.
Full Ontario visa guide →🆘 Emergency
911
💱 Currency
US Dollar ($)
🕐 Time zone
UTC−5 to −10
🗣️ Language
English
🔌 Plugs
Type A/B · 120V
🚗 Driving
Right side
💡 Tipping
Expected — 15–20% at restaurants
📞 Dial code
+1
Entry rules can change — always confirm with official sources before booking.
Stay connected in Ontario
Skip roaming fees — get a local eSIM before you land. Works in 200+ countries and activates instantly, so you’re online the moment you touch down.
Travel insurance
Protect your Denver to Ontario trip against delays, cancellations, and medical emergencies. US travelers can compare plans from top insurers.
Airport transfer in Ontario
Pre-book your ride into Ontario. Fixed price, meet & greet, and a driver waiting at arrivals — no meter anxiety after a long flight.
Flight delayed or cancelled?
If your Denver to Ontario flight was delayed more than 3 hours or cancelled, you may be entitled to up to €600 in compensation under EU/UK rules — even if you flew a non-EU airline. Free to check, no win no fee.
More resources
Denver to Ontario — frequently asked
How much is a flight from Denver to Ontario?+
Fares start around $190 round-trip, ranging up to about $280 in peak periods. Prices update daily across 800+ airlines.
What is the cheapest month to fly Denver to Ontario?+
July typically has the lowest fares, while August is the most expensive (around +22%).
Are there direct flights from Denver to Ontario?+
Yes — direct flights are available on this route. Connecting itineraries are often cheaper.
Which airlines fly from Denver to Ontario?+
Carriers on this route include Frontier Airlines. Compare them side by side in the search above.
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