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December travel from Denver International Airport (DEN) to Ontario International Airport (ONT) combines winter departure considerations with holiday peak demand. Expect increased passenger volumes, early morning and evening flights to Southern California, and winter weather coordination. This route is popular for holiday visits and connecting to Southern California attractions like Anaheim and Los Angeles.
Arriving at Ontario International Airport (ONT) in December places you within easy reach of Southern California holiday attractions, major shopping centers, and theme parks. Expect mild weather but holiday traffic; plan transfers to Los Angeles, Anaheim, Riverside, or San Diego with extra time. ONT serves as a practical alternative to LAX during busy December periods.
December brings holiday markets, lights, and winter attractions to both Denver and Southern California. In Denver, highlights include holiday markets, Denver Zoo Lights, and seasonal performances. Near Ontario (ONT), visitors can enjoy Disneyland's holiday offerings in Anaheim, Riverside's Festival of Lights, holiday parades in Los Angeles, and seasonal shopping at Ontario Mills and Victoria Gardens. These events increase traveler demand—book attractions and transport in advance.
The best time to fly DEN to ONT in December is midweek (Tuesday–Thursday) and early in the month to avoid peak holiday surges. Early morning outbound flights from Denver tend to have better on-time performance before afternoon snow events and air traffic build-up. For cost savings, look for flights in the first two weeks of December or consider red-eye options; for reliability, prioritize morning departures and allow extra buffer for weather.
Nonstop flights from Denver International Airport (DEN) to Ontario International Airport (ONT) are fastest (about 2h 10m–2h 30m) and minimize the risk of missed connections during December weather. Connecting itineraries can be cheaper or necessary when nonstop seats are sold out; common connection hubs include Phoenix (PHX), Los Angeles (LAX), Salt Lake City (SLC), and Las Vegas (LAS). If traveling during snowy conditions, prioritize nonstop flights for reliability or allow longer layovers if connecting through snow-affected hubs.
Popular carriers on the DEN to ONT corridor in December often include Southwest Airlines, Alaska Airlines, American Airlines, and United Airlines (schedule-dependent). Southwest and Alaska frequently offer competitive nonstop fares and flexible change policies, while legacy carriers may provide more frequent connections and premium cabin options. Consider baggage fees, loyalty program benefits, and on-time performance when selecting an airline during holiday travel.
Travelers flying DEN to ONT in December should prepare for winter weather at departure and holiday crowds at both airports. Pack warm layers, a compact umbrella for Southern California rain, and essential documents in a carry-on. Allow additional connection time if originating from mountain airports, and opt for refundable or flexible fares when possible. Use airline apps for real-time updates and enroll in airline text/flight alerts.
Nonstop flights between Denver International Airport (DEN) and Ontario International Airport (ONT) typically take about 2 hours 10 minutes to 2 hours 30 minutes depending on winds and routing. In December airlines often operate 3–6 daily nonstop flights on this route, with increased frequency during holiday weekends. Connecting flights via hubs such as Phoenix (PHX), Los Angeles (LAX), Salt Lake City (SLC), or Las Vegas (LAS) can add 1–4+ hours of layover time.
To find cheap DEN to ONT flights in December, book 4–8 weeks in advance and target midweek departures (Tuesday–Thursday) for lower fares. Early December (first two weeks) is often cheaper than peak holiday windows around Christmas and New Year. Use fare alerts, flexible date searches, and compare low-cost carriers like Southwest and Alaska with legacy carriers. Consider flying into nearby airports (LAX, SNA, SAN) and combining with a short ground transfer if nonstop fares are high.