Expect security screening at STL to take 5-10 minutes during off-peak times. Check real-time wait times online before heading to the airport.

Most accurate provider | Gotogate 3 stars |
|---|---|
Most trusted provider | Gotogate 3 stars |
Round-trip from | $268 (Kiwi.com) |
One-way from | $71 (Kiwi.com) |
Popular in | November |
Cheapest in | September |
Average price | $436 |
Good round-trip deal | $506 or less |
Good one-way deal | $350 or less |
Fly from
Fly to
Route
Depart
Return
Price
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Wed 2/11
5:55 pm-9:25 pm
Nonstop2h 30m
Boston Logan Intl
Wed 2/18
6:25 am-8:45 am
Nonstop3h 20m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Thu 4/16
9:10 am-5:26 pm
1 stop7h 16m
Boston Logan Intl
Tue 4/21
6:25 pm-11:57 pm
1 stop6h 32m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Wed 2/11
8:30 am-2:17 pm
1 stop4h 47m
Boston Logan Intl
Wed 2/18
6:00 am-12:21 pm
1 stop7h 21m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Sun 2/15
6:40 pm-10:10 pm
Nonstop2h 30m
Boston Logan Intl
Wed 2/18
6:50 am-1:55 pm
1 stop8h 05m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Tue 3/17
6:45 pm-10:10 pm
Nonstop2h 25m
Boston Logan Intl
Sun 3/22
5:35 am-7:40 am
Nonstop3h 05m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Tue 2/17
2:20 pm-10:55 pm
2 stops7h 35m
Boston Logan Intl
Mon 2/23
12:00 pm-8:00 pm
2 stops9h 00m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Tue 2/24
11:55 am-10:05 pm
2 stops9h 10m
Boston Logan Intl
Thu 2/26
9:00 am-5:15 pm
2 stops9h 15m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Fri 4/24
7:20 am-12:40 pm
1 stop4h 20m
Boston Logan Intl
Tue 4/28
12:55 pm-7:20 pm
1 stop7h 25m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Thu 5/14
9:55 am-6:15 pm
1 stop7h 20m
Boston Logan Intl
Sun 5/17
11:35 am-1:30 pm
Nonstop2h 55m
St. LouisBoston
STL - BOS
STLBOS
Lambert-St Louis
Wed 3/11
11:32 am-11:41 am
1 stop23h 09m
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy2 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*1 star | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star |
The best time to book flights from St. Louis to Boston is 79 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.
Currently, January is the cheapest month in which you can book a flight from St. Louis to Boston (average of $165). Flying from St. Louis to Boston in March is currently the most expensive (average of $283). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
A simple way to save on the total cost of your ticket is to fly from St. Louis to Boston in the evening. If you’re flexible enough to do this you can expect to save up to 59% on your trip compared to booking a flight at noon.
Travelers seeking maximum savings on their St. Louis to Boston flight should consider departing on Thursday evenings when fares are most often at their lowest. Monday at noon flights should be avoided if possible as fares are typically the most expensive at this time.
Entertainment
Food
Comfort
Boarding
Overall
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Entertainment
Food
Comfort
Boarding
Overall
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Entertainment
Food
Comfort
Boarding
Overall
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Entertainment
Food
Comfort
Boarding
Overall
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Entertainment
Food
Comfort
Boarding
Overall
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
Entertainment
Food
Comfort
Boarding
Overall
Crew
Reviews
Thomas,Dec 2025
SEA - DEN
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$73 | Average$249 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$75 | Average$250 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$118 | Average$284 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$153 | Average$311 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$277 | Average$435 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$303 | Average$458 | FlexibilityNo cancel fee | On-time63% |