Flights to Southwest Illinois from Boston - ￥19,970

View ￥19,970 flight on Wed, Sep 10, 2025Opens in a new window

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Cheap Flights from Boston to Southwest Illinois (BOS-STL)

Prices were available within the past 7 days and start at ￥19,970 for one-way flights and ￥34,230 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Wed, Sep 10 - Mon, Sep 15
BOS
Boston
STL
St. Louis
￥34,230 Roundtrip, found 2 days ago
￥34,230
Roundtrip
found 2 days ago
Select American Airlines flight, departing Wed, Sep 10 from Boston to St. Louis, returning Mon, Sep 15, priced at ￥34,230 found 2 days ago
American Airlines
Wed, Sep 10 - Mon, Sep 15
BOS
Boston
STL
St. Louis
￥37,120 Roundtrip, found 2 days ago
￥37,120
Roundtrip
found 2 days ago
Select American Airlines flight, departing Wed, Sep 10 from Boston to St. Louis, returning Mon, Sep 15, priced at ￥37,120 found 2 days ago
American Airlines
Wed, Sep 10 - Mon, Sep 15
BOS
Boston
STL
St. Louis
￥37,570 Roundtrip, found 2 days ago
￥37,570
Roundtrip
found 2 days ago
Select American Airlines flight, departing Wed, Sep 10 from Boston to St. Louis, returning Mon, Sep 15, priced at ￥37,570 found 2 days ago
American Airlines
Wed, Sep 10 - Mon, Sep 15
BOS
Boston
STL
St. Louis
￥39,730 Roundtrip, found 2 days ago
￥39,730
Roundtrip
found 2 days ago
Select American Airlines flight, departing Wed, Sep 10 from Boston to St. Louis, returning Mon, Sep 15, priced at ￥39,730 found 2 days ago
Delta
Tue, Aug 26 - Tue, Sep 9
BOS
Boston
STL
St. Louis
￥39,940 Roundtrip, found 1 day ago
￥39,940
Roundtrip
found 1 day ago
Select Delta flight, departing Tue, Aug 26 from Boston to St. Louis, returning Tue, Sep 9, priced at ￥39,940 found 1 day ago
United
Wed, Sep 10 - Mon, Sep 15
BOS
Boston
STL
St. Louis
￥45,910 Roundtrip, found 2 days ago
￥45,910
Roundtrip
found 2 days ago
Select United flight, departing Wed, Sep 10 from Boston to St. Louis, returning Mon, Sep 15, priced at ￥45,910 found 2 days ago
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