Finding cheap flights from Chicago to Denver doesn’t have to be a frustrating treasure hunt. With the right strategies, insider knowledge, and a bit of flexibility, you can score incredible deals on this popular Midwest-to-Mountain route. Whether you’re heading to Denver for business, adventure, or a mountain getaway, this comprehensive guide will help you navigate the best booking practices, timing strategies, and lesser-known tricks that savvy travelers use to keep their airfare costs down.
The Chicago-Denver corridor is one of America’s busiest flight routes, with multiple airlines competing for your business. This competition is your greatest advantage. Understanding how airlines price tickets, when to book, and which tools to use can easily save you $100-300 per ticket. We’ve gathered insider advice from travel agents, aviation industry professionals, and frequent flyers to bring you the most current and effective money-saving strategies.
Best Times to Book Flights Chicago to Denver
Timing is everything when hunting for cheap flights from Chicago to Denver. Industry data reveals that booking 2-3 weeks in advance typically yields the best prices for domestic flights. However, this isn’t a hard rule—it’s more of a sweet spot. Airlines adjust pricing algorithmically based on demand, competitor pricing, and seat availability.
The day of the week matters significantly. Tuesday and Wednesday departures from Chicago are consistently cheaper than Friday, Saturday, and Sunday flights. This is because leisure travelers prefer weekend trips, driving up demand and prices. If your schedule allows flexibility, shifting your travel to midweek can save 15-30% on fares. Early morning flights (departing before 7 AM) and red-eye flights (departing after 10 PM) are also typically cheaper because fewer people want to travel at inconvenient times.
Seasonality plays a crucial role in Denver airfare pricing. Peak travel seasons include summer (June-August) when families vacation and ski season (December-February) when winter sports enthusiasts flock to Colorado. Shoulder seasons—spring (April-May) and fall (September-October)—offer significantly lower fares. If you’re flexible with your travel dates, visiting Denver in May or September can mean saving 30-50% compared to peak season prices.
Book during airline sales events, which typically happen on Tuesday mornings. Airlines announce flash sales and promotional fares throughout the week, but Tuesday is when most major carriers release their weekly deals. Sign up for airline newsletters and enable price alerts on booking platforms to catch these sales before they disappear.
Airlines and Direct Routes
The Chicago-Denver route is served by several major carriers, each with different pricing strategies and frequent flyer programs. United Airlines, Southwest Airlines, and Frontier Airlines dominate this route with direct flights from Chicago’s O’Hare International Airport (ORD) and Midway International Airport (MDW) to Denver International Airport (DEN).
United typically offers more direct flights and premium services but often carries higher base fares. Southwest is known for customer-friendly policies like free checked bags and free cancellations, which can add value even if the base fare isn’t the absolute cheapest. Frontier and Spirit Airlines offer the lowest base fares but charge for almost everything—baggage, seat selection, boarding priority—so calculate the total cost before booking.
For budget-conscious travelers, Southwest remains an excellent choice because their “bags fly free” policy and two free checked bags save families and heavy packers significant money compared to competitors. If you’re flying solo with just a carry-on, Frontier’s rock-bottom fares might actually be cheaper overall.
Direct flights from Chicago to Denver typically take 2.5-3 hours and are available multiple times daily. While direct flights cost more than connecting flights, the time savings and reduced hassle often make them worth the premium. However, if you’re ultra-budget-conscious, connecting through cities like Kansas City or Dallas can sometimes yield cheaper fares, though you’ll sacrifice convenience.
Money-Saving Booking Strategies
Beyond timing, specific booking strategies can unlock substantial savings. Incognito mode is your friend—websites use cookies to track your searches and may show you higher prices if they know you’ve been looking at a route repeatedly. Clear your browsing history or use incognito mode when searching for flights to prevent dynamic pricing from inflating fares based on your search behavior.
Consider booking one-way tickets separately rather than round-trip packages. While this seems counterintuitive, airline pricing algorithms sometimes price one-way tickets cheaper than round-trip bundles, especially if the outbound and return flights have different demand levels. This strategy requires more research but can yield significant savings.
Price alerts are essential. Set up notifications on Google Flights, Kayak, and Skyscanner to track Chicago-Denver flights. These tools let you monitor prices for specific dates or entire months, showing you price trends so you can identify when fares drop. Many travelers find that watching price movements for a week or two before booking helps them identify the optimal booking window.
Join airline loyalty programs even if you don’t fly frequently. United MileagePlus, Southwest Rapid Rewards, and Frontier’s Frontier Miles programs offer free accounts with no commitment. Members often get access to exclusive flash sales, bonus mile promotions, and sometimes discounted fares. You might earn enough miles for a free flight to Denver after just a few trips from Chicago.
Leverage credit card sign-up bonuses if you’re willing to open a new travel credit card. Many cards offer 50,000+ bonus points worth $500-750 in travel value, easily covering a Chicago-Denver flight. Just ensure you’re comfortable with annual fees and usage patterns before applying.
Consider booking through third-party booking sites like Expedia, Kayak, or Orbitz, but compare their prices against booking directly with airlines. Some sites offer lower fares due to volume discounts, while others tack on hidden fees. Reading reviews and checking the fine print prevents surprises during checkout.
Tools and Resources for Finding Deals
Google Flights is the gold standard for flight searching. Its calendar view shows the cheapest day to fly within a month, its price tracking sends alerts when fares drop, and its flexible dates feature lets you search an entire month at once. For Chicago-Denver flights, Google Flights’ “best time to book” indicator provides data-driven recommendations.
Skyscanner excels at comparing prices across multiple airlines and booking sites simultaneously. Its “everywhere” feature lets you search all destinations from Chicago, useful if you’re flexible about where you fly. Skyscanner also shows historical price data, helping you understand whether current fares are good deals or likely to drop.
Kayak and Hopper offer price prediction features. Hopper uses machine learning to predict whether fares will rise or fall, telling you whether to book now or wait. While predictions aren’t perfect, they’re remarkably accurate and help you make confident booking decisions.
Airline websites directly sometimes offer exclusive deals unavailable on third-party sites. Check United.com, Southwest.com, and Frontier.com directly, especially for flash sales. Many airlines offer “airline only” fares that booking sites can’t access.
Twitter and travel blogs often announce flash sales minutes after airlines post them. Following @FrontierAirways, @United, @SouthwestAir, and deal-hunting accounts like @airfarewatchdog helps you catch limited-time promotions before they sell out.
Alternative Airports and Routes
While flying directly from Chicago’s major airports seems obvious, exploring alternatives can reveal cheaper options. Chicago Midway Airport (MDW) is smaller and less congested than O’Hare, often offering lower fares. Southwest operates heavily from Midway, and their competitive pricing on this route makes Midway worth checking.
Denver International Airport (DEN) is the main hub, but if you’re flexible, consider flying into Colorado Springs Airport (COS), about 90 minutes south of Denver. Flights to Colorado Springs are sometimes cheaper, and rental car savings might offset the longer drive. Similarly, flying to alternative mountains destinations and driving to Denver could work if you’re planning a broader Rocky Mountain adventure.
The Chicago-Denver route is short enough that you might consider driving or taking a scenic road trip instead of flying. It’s roughly 15 hours of driving—long but doable in two days. If you factor in airport parking, TSA wait times, and baggage fees, driving might actually be competitive with flying, especially for groups.
Connecting flights through hub cities like Phoenix or Las Vegas occasionally offer cheaper fares than direct flights, particularly during off-peak times. However, you’ll sacrifice 2-4 hours of travel time, so the savings must be substantial to justify the inconvenience.
Hidden Fees and How to Avoid Them
The cheapest advertised fare isn’t always the cheapest total price. Baggage fees are the biggest hidden cost. Southwest includes two free checked bags, while United and Frontier charge $35-45 for the first bag and $50+ for subsequent bags. A family of four with one checked bag each could pay $140-180 in baggage fees on United or Frontier.
Seat selection fees range from $10-30 per flight on budget carriers. While standard economy seats are free, preferred seats (extra legroom, better location) cost extra. If you’re tall or value comfort, budget for seat selection; otherwise, stick with standard assignments.
Carry-on restrictions on ultra-budget carriers like Spirit and Frontier are strict. Personal items are free, but standard carry-on bags incur fees. Packing everything into a small backpack or crossbody bag avoids these fees.
Change and cancellation policies vary dramatically. Southwest allows free changes and cancellations, while United charges $75-125 for changes and Spirit charges $99+. If you’re uncertain about your travel dates, Southwest’s flexibility justifies a slightly higher base fare.
Travel insurance isn’t mandatory but protects against unexpected changes. For a Chicago-Denver flight, travel insurance costs $20-40 and covers medical emergencies, trip cancellations, and lost baggage. It’s optional but worthwhile if your plans are flexible.
When comparing fares, use booking sites’ “total price” or “all fees included” filters to see the real cost. This prevents sticker shock at checkout and ensures you’re comparing apples-to-apples across airlines and booking methods.
FAQ
What’s the cheapest month to fly from Chicago to Denver?
April, May, September, and October typically offer the cheapest fares. These shoulder-season months have lower demand than summer and winter holidays while offering pleasant weather. Expect to save 30-50% compared to peak season prices.
How far in advance should I book Chicago-Denver flights?
Book 2-3 weeks in advance for the best prices. However, ultra-budget fares sometimes appear 4-6 weeks out during sales. Use price alerts to monitor trends and book when you find a good deal rather than waiting for a specific date.
Is Southwest or United cheaper for Chicago-Denver flights?
It depends on your total costs. United often has lower base fares, but Southwest’s free baggage and cancellations add value. Calculate total cost including fees before comparing. For budget-conscious travelers with light luggage, United might be cheaper; for families with baggage, Southwest usually wins.
Can I save money flying to Colorado Springs instead of Denver?
Sometimes. Colorado Springs flights might be $20-80 cheaper, but factor in the 90-minute drive to Denver (rental car gas, tolls) and it often evens out. Only pursue this if you’re staying in Colorado Springs or the savings exceed driving costs.
What time of day are Chicago-Denver flights cheapest?
Early morning (before 7 AM) and red-eye flights (after 10 PM) are typically cheaper than midday and evening flights. Early morning flights also get you to Denver by mid-morning, maximizing your day.
Should I book round-trip or one-way flights?
Usually round-trip is cheaper, but compare both. Sometimes booking two one-way tickets separately yields better total pricing, especially if outbound and return flights have different demand levels. Always check both options.
Do I need travel insurance for Chicago-Denver flights?
Travel insurance isn’t necessary for a short domestic flight, but it’s worthwhile if your plans are flexible or you’re traveling during uncertain times. For $20-40, it protects against cancellations and medical emergencies.
What’s the fastest way to get from Chicago to Denver?
Direct flights take 2.5-3 hours plus 2-3 hours for airport procedures (arriving early, security, baggage claim). Total door-to-door time is roughly 5-6 hours. Driving takes 15 hours but eliminates airport hassles for some travelers.