Top Airlines Offering Low Fares from Chicago to San Francisco

When it comes to finding the best deals on flights from Chicago to San Francisco, knowing which airlines consistently offer low fares can make all the difference. Whether you're planning a business trip, a weekend getaway, or a longer vacation, here’s a guide to the top airlines that provide affordable options for this popular route.

1. Southwest Airlines

• Low Fare Calendar: Southwest is well-known for its "Low Fare Calendar," which allows you to see the cheapest flights over a range of dates. This tool is incredibly useful for flexible travelers looking to find the best deals.
• No Change Fees: Southwest’s no change fee policy is a significant advantage. You can adjust your travel dates without worrying about hefty penalties, making it easier to take advantage of last-minute deals.
• Free Checked Bags: Unlike many other airlines, Southwest includes two free checked bags with every fare, potentially saving you $60 or more per trip.

2. United Airlines

• Hub Advantage: United Airlines, headquartered in Chicago, often offers competitive prices on flights to San Francisco. Being a major hub, Chicago O'Hare International Airport (ORD) is a central point for United, leading to multiple daily flights with varying price points.
• MileagePlus Program: Frequent flyers can benefit from the MileagePlus program, where accumulated miles can be used to book future flights at lower prices.
• Basic Economy Fares: For budget-conscious travelers, United's Basic Economy fares are often among the lowest, though they come with some restrictions, such as limited seat selection and no carry-on baggage.

3. American Airlines

• Competitive Pricing: American Airlines frequently offers low fares on this route, especially during off-peak seasons and through various sales events.
• AAdvantage Loyalty Program: Members of the AAdvantage program can earn miles that can be redeemed for future travel, upgrades, and other perks. This can lead to significant savings over time.
• Economy Web Specials: These limited-time offers are designed to provide low fares on specific routes, including Chicago to San Francisco. They’re available exclusively to Advantage members and often include last-minute deals.

4. Delta Air Lines

• Dynamic Pricing: Delta’s pricing model often includes fluctuating fares that can be advantageous for those booking at the right time. Their Fly Delta app allows you to track fare changes easily.
• SkyMiles Program: Delta’s frequent flyer program, SkyMiles, offers opportunities to earn miles on every flight, which can then be redeemed for discounts on future trips.
• Flash Sales: Delta occasionally runs flash sales, where low fares from Chicago to San Francisco can drop significantly for a short period. Signing up for alerts can ensure you don’t miss these deals.

5. Spirit Airlines

• Ultra-Low-Cost Carrier: Spirit is famous (or infamous) for its ultra-low-cost fares. If you’re looking to get from point A to point B with minimal expense, Spirit is hard to beat.
• Bare Fare Pricing: Spirit’s pricing is a la carte, meaning you only pay for what you need. While this can be beneficial for those traveling light, be aware of additional fees for bags, seat selection, and other services.
• Big Front Seat Option: For a more comfortable flight at a lower cost than traditional first-class seats, Spirit offers the Big Front Seat, which provides extra legroom and wider seats.

6. Alaska Airlines

• Mileage Plan: Alaska’s Mileage Plan is one of the most generous frequent flyer programs, allowing you to earn miles based on the distance flown rather than the cost of the ticket.
• Saver Fares: These low-cost options come with some restrictions, such as no changes or cancellations, but they often offer the cheapest way to fly between Chicago and San Francisco.
• Partner Airlines: Alaska Airlines partners with several international carriers, which can be advantageous for those planning to extend their journey beyond San Francisco.

7. JetBlue Airways

• Blue Basic Fares: JetBlue’s Blue Basic fares are often very competitive, especially if you’re booking well in advance. These fares are similar to Basic Economy on other airlines but often include more perks, like free Wi-Fi.
• TrueBlue Loyalty Program: JetBlue’s loyalty program allows you to earn points on every flight, which can be redeemed for future travel. Points don’t expire, making it a good option for occasional travelers.
• Mint Service: For those willing to splurge a little, JetBlue’s Mint service offers a premium experience with lie-flat seats, artisanal dining, and other high-end perks, often at a lower price point than traditional first-class offerings.

8. Frontier Airlines

• Discount Den: Frontier’s membership program, Discount Den, gives you access to exclusive low fares and family-friendly perks like Kids Fly Free deals.
• Bundled Options: Frontier offers "The Works" and "The Perks" bundles, which include benefits like seat selection, checked bags, and priority boarding. These can be cost-effective if you need those services.
• Flexible Booking: Frontier’s flexible booking options allow you to adjust your plans without incurring significant costs, which can be a major advantage if your schedule is uncertain.

9. Allegiant Air

• Direct Flights: While Allegiant doesn’t offer daily service, its direct flights from smaller airports in the Chicago area (like Rockford or MidAmerica St. Louis) to Oakland or San Francisco International Airport can be a budget-friendly alternative.
• Bundled Savings: Allegiant often offers discounts when booking flights along with hotels, car rentals, or activities, allowing you to save on your entire trip.
• Low Base Fares: Allegiant's no-frills approach to pricing means their base fares are often among the lowest available, though be mindful of additional fees for services like seat selection and baggage.

10. Sun Country Airlines

• Affordable Charters: Sun Country operates a mix of scheduled flights and charter services, which can sometimes result in lower fares due to reduced overhead costs.
• Ufly Rewards: Sun Country’s loyalty program, Ufly Rewards, allows you to earn points on every flight, which can be redeemed for discounts on future travel.
• Seasonal Offers: Sun Country often runs seasonal promotions that include low fares on specific routes, including Chicago to San Francisco. These promotions are typically announced via email, so signing up for alerts is recommended.