Cheap flights from San Antonio to Chicago from $136

The month of September is, on average, the cheapest month to fly to Chicago from San Antonio, with most prices found around $305. If you’re not able to fly to Chicago in September, then February is your next best option. Flight prices from San Antonio to Chicago during February average around $314.

The cheapest day to depart on your flight to Chicago is on a Thursday when prices can be found for as low as $449. This is often the case because there is less demand to fly during this day of the week. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from San Antonio to Chicago for around $809.

Our most recent data shows that the best time of day to fly to Chicago is in the morning. Flights from San Antonio to Chicago during this time can be as low as $476. In contrast, the most expensive time of day to depart to Chicago is at noon when prices are around $812.

Fly from San Antonio to Chicago O'Hare Intl for the best San Antonio - Chicago flight prices

You are more likely to see cheaper flights to Chicago from San Antonio when booking weeks ahead of your departure date. In general, you can expect to find flights to Chicago for around $381 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Chicago from San Antonio for as low as $294 on momondo.

There are 4 cabin classes available to choose from on San Antonio to Chicago flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

You could potentially save up to 1% on your flight if you consider stops on a San Antonio to Chicago flight.

As of April 2026, prices for San Antonio to Chicago flights are approximately 16% more expensive when compared to flights at the same time last year.

Frontier, Southwest, and United Airlines are the most popular carriers operating from San Antonio to Chicago

American Airlines, United Airlines and Frontier are the top three most popular airlines that fly to Chicago from San Antonio according to our data. American Airlines is the first choice among our users, with 43% of people opting to fly with this airline when traveling to Chicago. Keep in mind that there are 5 different airlines that fly to Chicago on a routine basis, so you have a few additional options to choose from.

Fort Lauderdale (FLL) was the most common stop: 53% of momondo users choosing 1-stop flights on this route connected there.

Flights via Atlanta (ATL) offer the lowest average round-trip price of $160.

Flights connecting via Atlanta (ATL) have the shortest average one-way travel time: 6h 16m.

Atlanta (ATL) has the shortest average layover time for this route: 2h 25m.

As of April 2026, 20 flights take off from San Antonio and land in Chicago each day. The most common flight departure time for this route is 1:00PM, with 61% of daily flights taking off in the afternoon.

145 flights are operational weekly from San Antonio to Chicago as of April 2026. The most popular departure day for this route is Mon, with 20% of flights per week taking off on this day.