CMI to SFO, University Of Illinois Willard Airport to San Francisco International Airport Cheap Flights

Based on HopeGoo data, American Airlines offers one-way fares as low as US$296 on Cheapest nonstop routes (e.g. CMI to SFO on Wed, Mar 18), while American Airlines offers Cheapest nonstop round-trips from US$498 departing on Sun, Mar 1 and returning on Sat, Mar 7.

By analyzing data from all airlines on the HopeGoo flight calendar, it looks like the best time to book a flight from Champaign to San Francisco is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.

To find best deals on flights from Champaign to San Francisco, you can use various tools on HopeGoo: · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Wed, Mar 18, with one-way flights priced at just US$296. · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is American Airlines. · Set up price alerts to easily monitor ticket prices without having to check every day. · Check HopeGoo flight deals and promo codes frequently. · Avoid peak season unless you book very early. It seems the peak season for San Francisco travel is around November. · Get exclusive promo codes for HopeGoo app users.

The cheapest months to fly from Champaign to San Francisco is December, when demand for travel is lower.

After crunching the numbers on our February flight calendar, it's currently cheapest to fly from Champaign to San Francisco on February 27, 2026 with American Airlines, with prices starting at US$588.

The time difference between San Francisco and Champaign is 2h.

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