A sunset over a snowy landscape with a river and sparse trees.

$20 Cheap Flights to Thornton, CO

View $20 flight on Wed, Nov 11, 2026Opens in a new window

Popular airlines to Thornton

How much is the cheapest flight to Thornton?

Prices were available within the past 7 days and start at $20 for one-way flights and $38 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Southwest Airlines
Sun Country Airlines
American Airlines
Delta

Alternative airports near Thornton

Prices were available within the past 7 days. Prices and availability are subject to change.

Find the cheapest month to fly from Columbus (CMH) to Denver (DEN)

From $162 - $328 per traveler.

What you need to know for your flight to Thornton

Flights to Thornton at a glance

Traveling to Thornton is easy—select from a range of airlines, including options for cheap flights to Thornton and flights to Denver. Compare travel times and choose the best fit for your budget and itinerary as you plan to explore the city’s renowned attractions and neighborhoods.

  • Major airport near Thornton: Denver International Airport (DEN)
  • Flights per week: 6,750+ flights arriving at Thornton airport
  • Number of airlines that fly to Thornton: around 65+ carriers

Popular airport near Thornton

Thornton is a vibrant city perfect for family getaways, business trips, and city vacations. Visitors are drawn to its entertainment options, sports activities, and outdoor adventures. The city is conveniently accessible via a major airport, making it easy for travelers to find the closest airport to meet their travel needs.

  • Denver International Airport (DEN): Situated in Denver County, Colorado, approximately 16 miles from Thornton, this airport caters to both domestic and international flights, linking travelers to over 295 domestic cities and more than 200 international destinations. Passengers have the option to enhance their travel experience by upgrading to first class, premium economy, or business class seating, depending on the airline and route chosen. Notable airlines that operate from this airport include United, Frontier Airlines, and Southwest Airlines.

Top routes to Thornton

  • New York (JFK/LGA) to Thornton (DEN), with one-way tickets available from around $85
  • Chicago (ORD/MDW) to Thornton (DEN), with one-way flights starting at around $50
  • Los Angeles (LAX) to Thornton (DEN), with one-way flights starting at around $45
  • Boston (BOS) to Thornton (DEN), with one-way fares starting at around $90
  • Dallas (DFW/DAL) to Thornton (DEN), with one-way flights starting at around $35

Cheapest routes to Thornton

  • Vail (EGE) to Thornton (DEN), with low one-way fares from around $25
  • Dallas (DFW/DAL) to Thornton (DEN), with cheap one-way fares from around $35
  • Salt Lake City (SLC) to Thornton (DEN), with budget one-way fares from around $35
  • El Paso (ELP) to Thornton (DEN), with cheap one-way fares from around $35
  • San Diego (SAN) to Thornton (DEN), with affordable one-way prices from around $35

*Flight times and fares vary by season and availability and are based on one-way routes

Top airlines with flights to Thornton

  • United: Operating flights to Denver International Airport (DEN), United represents about 38% of arrivals in Thornton. The typical one-way fare hovers around $360, with premium cabin choices like premium economy, business, and first class available based on the route.
  • Southwest Airlines: Also servicing Denver International Airport (DEN), Southwest Airlines accounts for roughly 21% of arrivals to Thornton. Travelers can expect an average one-way fare of about $200.
  • Frontier Airlines: Flying to Denver International Airport (DEN), Frontier Airlines makes up around 12% of Thornton's arrivals. The average one-way fare is approximately $140, providing a budget-friendly option for passengers.
  • American Airlines: Servicing Denver International Airport (DEN), American Airlines contributes about 12% of arrivals to Thornton. With an average one-way fare of roughly $360, travelers can access first-class service depending on the route.
  • Delta: Providing flights to Denver International Airport (DEN), Delta accounts for approximately 10% of arrivals in Thornton. The average one-way fare is around $310, with premium cabin service options including premium economy, business, and first class, contingent on the route.

Best time to fly to Thornton

The most popular months for travelers to fly to Thornton are January, March, and April, when peak temperatures in Thornton can reach up to 46.9°F in April. If you prefer quieter travel, consider September, the least busy time to visit with temperatures around 66.2°F and typically the lowest average one-way fare (around $177), roughly 9% cheaper than the yearly average. Looking for additional cheaper months to fly? October, August, and February offer average one-way fares of around $184, making them good options for flexible travelers.

calendar iconMonthtemperature iconTemperaturerain iconPrecipitationmostly cloudy iconCloudinesscrowd level iconDemandprice iconAverage one-way Fare
January28.2°F (-2.1°C)No Rain (Dry)Mostly SunnyModerately High$203
February28.9°F (-1.7°C)No Rain (Dry)Mostly SunnyAverage$188
March39.6°F (4.2°C)No Rain (Dry)Mostly SunnyModerately High$216
April46.9°F (8.3°C)Light RainMostly SunnyModerately High$198
May55.8°F (13.2°C)Light RainMostly SunnyModerately Low$189
June68.7°F (20.4°C)Light RainSunnyAverage$204
July74.1°F (23.4°C)Light RainSunnyAverage$196
August72.9°F (22.7°C)No Rain (Dry)SunnyAverage$185
September66.2°F (19.0°C)No Rain (Dry)SunnyModerately Low$177
October50.5°F (10.3°C)No Rain (Dry)SunnyAverage$181
November38.5°F (3.6°C)No Rain (Dry)SunnyModerately Low$194
December28.9°F (-1.7°C)No Rain (Dry)SunnyAverage$212

*Average one-way fare is based on Expedia flight booking data from January 2025 to April 2026 for the specified route and travel class and may change depending on availability, dates, and demand.

How to save money on a flight to Thornton

Getting some of the best deals on flights to Thornton is all about timing and flexibility. Here are some key tips to help you save:

  1. Compare flight options—use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
  2. Set up price alerts—as an Expedia member you can use Price Tracking to receive notifications when flight prices change.
  3. Bundle and save—book a flight and unlock a hotel deal on Expedia*, or explore our Thornton hotel and flight deals.
  4. Think about luggage-nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your baggage allowance before confirming your booking to avoid excess baggage fees at the airport.
  5. Earn miles—you can earn airline miles when you book your Thornton flight with Expedia. Just select your frequent flyer program and enter your program number when confirming your booking.

*For members. Select hotels.

Arriving in Thornton

Thornton welcomes travelers through its range of transport options based on price, convenience, and proximity. Here's how to reach Thornton efficiently:

  • Public transportation: From Denver International Airport, Jeppesen Terminal Station, a metro station, is conveniently located just 0.1 miles from the airport, providing easy access for travelers.
  • Hotel transfer: Transfers offer a convenient way to reach your hotel in Thornton, with private rides that can be arranged in advance.
  • Car rental: Renting a car in Thornton is a good option if you plan to explore and sightsee beyond the city. Browse cheap car rentals in Thornton on Expedia.
  • Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.

Where to stay in and around Thornton

  • Denver: As a vibrant metropolis, Denver offers a multitude of outdoor adventures, entertainment options, and cultural experiences. Located in the heart of the Rocky Mountain region, travelers flock to Denver for its stunning natural landscapes and lively atmosphere. Key attractions include the historic Union Station, the breathtaking Red Rocks Amphitheater, and the expansive Colorado Convention Center. Whether you're looking to catch a game at a local sports stadium or explore nearby national parks, Denver serves as the perfect base for a memorable trip.
  • Broomfield: Broomfield is located 6 miles drive away from Thornton and is an inviting city known for its family-friendly atmosphere and outdoor spaces. Visitors can enjoy activities at the Broomfield County Commons Dog Park or delve into the local history at the Broomfield 9-11 Memorial. With a mix of urban parks, shopping centers, and educational institutions, Broomfield provides a well-rounded experience for travelers seeking both relaxation and cultural enrichment.
  • Vista Ridge: Vista Ridge is located 14 miles drive away from Thornton and is a charming neighborhood ideal for outdoor enthusiasts and sports lovers. With access to scenic golf courses and modern entertainment facilities like Topgolf, Vista Ridge is a great spot for family outings or sporting events. Nearby landmarks, including the University of Colorado Boulder and the National Archives at Denver, enrich the area, making it a delightful destination for those looking to explore local culture while enjoying the outdoors.

Tips for short-haul flights to Thornton

For quick getaways, efficiency is key. Here is how to make your short-haul journey smoother:

  • Pack light and skip checked bags—with budget airlines, traveling with just a carry-on is often more economical. Maximize your space by using mini toiletries, wearing your bulkiest clothing, and planning your outfits wisely. This approach also allows you to bypass the wait at baggage claim upon arrival.
  • Bring your own entertainment—many short-haul flights may not provide in-flight entertainment options. To keep yourself occupied, download your favorite TV shows, movies, music, or podcasts ahead of time, and consider bringing a book. Remember to fully charge your devices before you board.
  • Arrive at the airport in plenty of time—even for short or domestic flights, it's advisable to arrive at least 1.5 to 2 hours prior to departure, taking into account traffic and security lines.
  • Bring your own snacks and water—pack some snacks and a refillable water bottle to stay hydrated and save money while at the airport.

Tips for long-haul flights to Thornton

Flying long-haul sometimes requires extra planning to ensure a comfortable journey:

  • Select your seat in advance—for longer flights, choosing your seat is essential for comfort. Full-service airlines often provide complimentary seat selection once online check-in opens, typically 24–48 hours before your flight. Some airlines may allow you to select your seat even earlier.
  • Arrive at the airport in plenty of time—make sure to arrive at the airport at least 3 hours prior to departure for international flights to accommodate check-in, security, and immigration processes.
  • Relax at the airport—if you have some extra time, take the opportunity to explore the shops, grab a coffee, or unwind at the gate or in a departure lounge if you have access. Most airports offer free Wi-Fi for your convenience.
  • Adjust to the new time zone mid-flight—begin syncing your body clock by changing your watch and sleep routine to align with your destination's time zone. Try to either sleep or stay awake during the flight according to the local time of your arrival to help minimize jet lag.

Frequently asked questions

What month is the cheapest to fly to Thornton?
Schedule your trip for September if you're hoping to get a deal on your fare. It's the cheapest month to fly to Thornton. If possible, avoid traveling during peak periods such as major public holidays or events.
Which US cities have the cheapest flights to Thornton?
Get cheap flights to Thornton from Chicago, Phoenix and Dallas. These cities usually offer the best fares to this popular destination. But remember that stopovers, seasonality and demand will also impact rates, so remain flexible and book when prices are right.
Which US cities fly direct to Thornton?
You can fly to Thornton directly from 164 US cities. To find a nonstop journey, check "Direct flights only" when looking for flights to Thornton on Expedia. Then, compare your choices and pick the best departure from any of these cities:
  • Chicago
  • Phoenix
  • Dallas
  • Las Vegas
  • Salt Lake City
How to find a cheap flight to Thornton?
Book in advance for the best chance of scoring cheap flights to Thornton. Also, consider traveling during off-peak months like December and January. If you leave on a Thursday, you can save 16% on average compared to those departing on a Sunday.* Save time checking every day and track your flight prices using the Expedia app. We'll send you a notification when fares change.*Best day of the week to book, depart and ideal booking window recommendations based on average round-trip ticket prices for January through August 2023, sourced from Airline Reporting Corporation's (ARC) global airline sales database. Percentages noted are averages.
How to get a cheap last-minute flight to Thornton?
Being flexible about your plans can help you to secure last-minute deals on cheap flights to Thornton. To view all the available options, consider exploring different ticket types, tweaking your Thornton trip dates, leaving from an alternative airport or going with another airline.
How far in advance should I book a flight to Thornton?
Secure your flight to Thornton two to four months ahead if you're taking off from an international destination. For domestic travel, the timeframe is around 28 days in advance. Cheaper tickets and a greater choice of departure dates, schedules and seating options are just some of the awesome benefits of booking early.**Best day of the week to book, depart and ideal booking window recommendations based on average round-trip ticket prices for January through August 2023, sourced from Airline Reporting Corporation's (ARC) global airline sales database. Percentages noted are averages.
Which day of the week is the cheapest day to buy a plane ticket to Thornton?
Sundays are generally the best day to book a cheap flight to Thornton, where you can save 8% on average compared to Fridays. If you choose to purchase on a Friday, expect to pay more as this is typically the most expensive day.**Best day of the week to book, depart and ideal booking window recommendations based on average round-trip ticket prices for January through August 2023, sourced from Airline Reporting Corporation's (ARC) global airline sales database. Percentages noted are averages.
Which airlines fly to Thornton?
Thornton is connected to 194 airports worldwide through 19 carriers, with Denver Intl. Airport (DEN) as its primary entry point. Select from these major airlines to Thornton when planning your trip:
  • United Airlines
  • American Airlines
  • Delta Air Lines
  • Frontier Airlines
Where do you fly into Thornton?
Thornton's main airport is Denver Intl. Airport (DEN). If you're looking for more nearby options when flying to Thornton, check out Broomfield, CO (BJC-Rocky Mountain Metropolitan), Boulder, CO (WBU-Boulder Municipal) or Centennial Airport (APA). It's also possible to fly to Thornton through Fort Collins, CO (FNL-Fort Collins-Loveland Municipal).
How far is the airport from central Thornton?
If you're jetting into Denver Intl. Airport (DEN), you'll be roughly 16 mi east of the center of Thornton.
Can I save money by booking a Thornton trip package?
Bundle your accommodations and flights and you could save hundreds of dollars. Better yet, you can add extras like tours and car rentals to your Thornton flight and hotel package deal. With Expedia, it's simple to look after all your Thornton travel arrangements in the same place.
Can I change or cancel my flight to Thornton?
It's often possible to cancel or change your flight to Thornton. Many airlines let you cancel flights for free within 24 hours of booking. However, some flights are non-refundable, and airlines may offer you credit for future flights in place of a direct refund. To reserve affordable flights to Thornton with flexible change policies, pick the "Changes included" or "No cancel fee" filters when you search. Want more details? Visit our Customer Service Portal.

*Flight schedules are subject to change.

*Available to One Key members.

Book with confidence

Tips to find the cheapest flights to Thornton

The cheapest day to fly

Get started finding a cheap flight to Thornton on Expedia by either choosing a deal on this page or entering into the search bar your travel dates, origin airport, and whether you want roundtrip or one-way airfare. You can filter for flexibility, number of stops, airline, and departure/arrival times to find the best flight for you.

The cheapest month to fly

September is the cheapest month to fly to Thornton. This coincides with the low season when fewer people travel. Whichever month you travel in, though, be sure to book at least a month in advance if you want to score cheap tickets to Thornton. ARC's data shows that domestic flights booked 28 days or more before departure are typically 24% cheaper than those booked last minute.

The most affordable time to book a flight

Typically, a Sunday can be the cheapest time to book a flight to Thornton, according to ARC’s data. On average, you could save between 6% and 13% by booking on a Sunday instead of a Friday, which is the most expensive day to make a reservation.

The cheapest round-trip tickets to Thornton

The lowest price for round-trip flights to Thornton in 2026 starts from from $38, while one-way tickets start from from $20. Expedia's effective search tool is one of the best ways to find a budget airfare. Simply enter your dates, and within seconds, it'll show you a vast selection of the cheapest flights to Thornton. If you have a preferred departure time or airline, you can use the handy filters to customize your search.

The cheapest airlines flying to Thornton

Frontier Airlines, United, Southwest Airlines, Sun Country Airlines, American Airlines, Delta are just some of the airlines that can typically offer cheap tickets to Thornton. You can find their most affordable flights by using the “airline” search filter and then sorting prices from low to high. As a trusted partner of the world's leading airlines, Expedia offers you some of the best airfare deals to Thornton and countless more destinations worldwide.

The most affordable airports to fly into

To view the cheapest airports to fly into for Thornton, simply order your search results from lowest to highest price. Expedia's search tool compares flight prices for all airports close to your destination, so you don't have to manually search them one by one to find the cheapest flight to Thornton. If you have a preferred place to fly into, take advantage of the “arrival airport” filter to narrow down your search on Expedia.

Save with a package

With Expedia's amazing package deals, you could save hundreds of dollars by booking your Thornton plane tickets together with your accommodations, car rental, or activities. Just select the search wizard's “package” option to view some of the cheapest deals. Look out for the green savings label to see how much you're saving.

Date flexibility for the cheapest flights to Thornton

If you can be flexible with your travel dates, it's a good idea to broaden your search by comparing prices on different days. This will open up more options, meaning you could uncover a less expensive flight to Thornton.

Stopover savings

The cheapest tickets to Thornton are sometimes those with a stopover. Book one of these flights, and you'll change planes at an airport en route to Thornton. While the overall travel time might be longer than a non-stop flight, you may decide it's worth it for the money saved.

Get Expedia's Price Drop Protection

Price Drop Protection means that if your flight gets cheaper after booking, you'll be credited the difference*. This gives you peace of mind that you're getting one of the cheapest flights to Thornton for your chosen departure. Expedia's Price Drop Protection is available for a small fee but is free to One Key Gold and Platinum tier members.

*Terms apply.

Use our Price Tracking feature

Expedia's Price Tracking feature is another great tool that removes the guesswork from finding cheap flights to Thornton. Simply download the free Expedia app to your smart device and activate Thornton flight price alerts for your travel dates. There's even a price predictor tool that uses historical data to indicate the best time to book, giving you peace of mind that you'll nab the lowest prices.

Book with Expedia

As well as Price Drop Protection and Price Tracking, Expedia's close partnership with a vast selection of the world's leading airlines means you're sure to find cheap flights to Thornton. Plus, the One Key rewards program lets you earn real cash rewards on most bookings that you can use to save money on future trips. Best of all, it's free to join, and members often unlock exclusive discounts, too.

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

Tips to find the cheapest flights to Thornton

Travel information

Destination airport
Denver Intl.
Destination airport IATA code
DEN
Destination city name
Denver
Roundtrip price
$38

Trending flights to Thornton

Prices were available within the past 7 days and start at $20 for one-way flights and $38 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines

Explore a world of travel with Expedia