Cheap flights from Seattle to Chicago from $126 BFI, SEA → MDW, ORD

Found recently, and the cheapest we hold

What have prices looked like?

Over 49 days, 24 Sept to 11 Nov, the cheapest return we saw each day was $211 to $388.

Those were the prices on those days, not today's.

Could nearby dates be cheaper?

We hold no other 22-night return fares leaving within 3 days of 12 Dec to compare.

Every date we hold

3 fares on 2 departure dates

Found recently, and the cheapest we hold

It is also the cheapest one-way we hold, of any age.

What have prices looked like?

Over 42 days, 24 Sept to 11 Nov, the cheapest one-way we saw each day was $88 to $447.

Those were the prices on those days, not today's.

Could nearby dates be cheaper?

No. We hold one-way fares on 1 other departure date within 3 days of 10 Dec, and it is not cheaper.

Every date we hold

6 fares on 3 departure dates

Which month looks cheapest?

December 2026 is the cheapest month — from $126.

Return

Fares 30 to 59 days before departure were typically 21% lower than 0 to 6 days before departure.

From the cheapest return each day between 24 Sept and 11 Nov (49 days), grouped by how many days ahead the flight left; one adult in economy.

Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.

Prices reflect recent searches — current fares may differ.

One-way

Fares 30 to 59 days before departure were typically 73% lower than 0 to 6 days before departure.

From the cheapest one-way each day between 24 Sept and 11 Nov (42 days), grouped by how many days ahead the flight left; one adult in economy.

Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.

Prices reflect recent searches — current fares may differ.

How much is a return flight from Seattle to Chicago?

The cheapest return found recently is $318 with Alaska Airlines, 12 Dec to 3 Jan 2027, found 4 days ago. The cheapest return we hold, of any age, is $292 with Frontier Airlines, 28 Dec to 4 Jan 2027, found 7 days ago.

How much is a one-way flight from Seattle to Chicago?

The cheapest one-way found recently is $126 with Alaska Airlines, 10 Dec, found 2 days ago. The cheapest one-way fare on each of 3 departure dates is usually $126 to $135.

What is the cheapest month to fly from Seattle to Chicago?

December 2026 is the cheapest month for a one-way, from $126, 10 Dec, found 2 days ago.

How far ahead should I book a flight from Seattle to Chicago?

In 49 days of prices between 24 Sept and 11 Nov, return fares 30 to 59 days before departure were typically 21% lower than 0 to 6 days before departure. In 42 days of prices between 24 Sept and 11 Nov, one-way fares 30 to 59 days before departure were typically 73% lower than 0 to 6 days before departure.

Is there a direct flight from Seattle to Chicago?

Yes, the cheapest nonstop return found recently is $318 with Alaska Airlines, 12 Dec to 3 Jan 2027, found 4 days ago. The cheapest nonstop one-way found recently is $126 with Alaska Airlines, 10 Dec, found 2 days ago.

How long is the flight from Seattle to Chicago?

The cheapest nonstop one-way found recently, with Alaska Airlines on 10 Dec, takes 3 h 57 min from Seattle-Tacoma International Airport (SEA) to O'Hare International Airport (ORD).

Which airlines have the cheapest flights from Seattle to Chicago?

Between 13 Nov and 11 Dec, Alaska Airlines has the cheapest one-way on all 3 departure dates we hold.