St. Louis Airport Security Wait Times & STL Queue Guide 2026

St. Louis Lambert Airport Security Wait Times Today

The St. Louis Lambert Airport security wait time estimates below show the typical STL queue at each checkpoint for this hour and day of week. St. Louis Lambert International Airport (STL/KSTL) operates two separate terminal buildings roughly one mile apart, with three security checkpoints across them. In Terminal 1, the Concourse A checkpoint serves Delta, United and Air Canada, and the Concourse C checkpoint serves American Airlines, Alaska Airlines and Frontier Airlines. In Terminal 2, a single Concourse E checkpoint handles all Southwest Airlines departures alongside Lufthansa and British Airways. Security wait times vary by checkpoint and across hours. The Concourse E checkpoint, which processes the largest share of STL passenger volume thanks to Southwest's roughly 60 percent market share at Lambert, sees the heaviest queues during morning Southwest departure banks.

How Long Is Security at St. Louis Lambert Airport?

Security wait times at St. Louis Lambert Airport depend on which checkpoint you use and what time you arrive. During the quiet midweek window from 09:00 to 15:00, most passengers clear the standard lane in 9 to 14 minutes at any of the three checkpoints. During the morning Southwest departure bank peak from 05:30 to 08:30, queues of 20 to 35 minutes are common in the standard lane at the Concourse E checkpoint in Terminal 2, which carries the heaviest load. Airport data confirmed through 2025 identifies 05:30 to 08:30 and 16:00 to 19:00 as the two daily pressure windows at STL. Saturdays around midday can also see waits approaching 29 minutes at the busiest checkpoint, driven by leisure travel patterns. Fridays, Mondays and Sundays experience the most acute pressure, while Sunday afternoons generate a pronounced return wave as St. Louis area travelers arrive back from weekend trips.

TSA PreCheck members at STL typically clear the dedicated PreCheck lane in under 8 minutes at most hours. CLEAR members who also hold PreCheck get the fastest experience available at Lambert: CLEAR handles the identity verification step at a biometric kiosk, sending you directly to the physical screening area, while PreCheck handles that screening without shoe, laptop or liquid removal required. CLEAR is confirmed at all three STL checkpoints. There is no terminal-specific paid priority pass at Lambert comparable to B-Fast at LaGuardia or similar products at other US airports. Any traveler who flies through STL more than two or three times a year and has not enrolled in TSA PreCheck is likely losing more time to queues than the cost of membership justifies, particularly during the Southwest morning peak at the Concourse E checkpoint.

A critical detail at St. Louis Lambert Airport is that the two terminals have no airside connection, and within Terminal 1 the two concourse checkpoints are also separate. If you clear the Concourse A checkpoint for a Delta flight and your connecting flight is on American Airlines in Concourse C, you must exit the secure area and re-enter through the Concourse C checkpoint. If your connection is in Terminal 2, you must exit, board the free inter-terminal shuttle bus and re-clear security at the Concourse E checkpoint, a process that takes 15 to 25 minutes including shuttle wait time. Always verify your terminal and concourse on your boarding pass before you leave for the airport. Concourse A: Delta, United, Air Canada. Concourse C: American, Alaska, Frontier. Concourse E: Southwest, Lufthansa, British Airways.

St. Louis Lambert Airport Security and the British Airways Launch

The most significant recent operational change at St. Louis Lambert Airport was the launch of British Airways nonstop service between St. Louis and London Heathrow on 19 April 2026. This makes STL one of a small number of US mid-size cities with direct transatlantic access to Heathrow, the first such service to Heathrow the airport has ever had. British Airways operates from Concourse E in Terminal 2, joining Lufthansa's Frankfurt nonstop that has been running since 2022. Both carriers depart from Terminal 2, so international passengers at STL should note that the Concourse E checkpoint in Terminal 2 is the correct entry point for all transatlantic departures. International arrivals on both Lufthansa and British Airways clear customs and border protection on the lower arrivals level of Terminal 2.

The addition of British Airways to the Concourse E lineup adds international passenger mix to a checkpoint already handling Southwest's substantial domestic volume. Passengers connecting inbound from Heathrow to onward Southwest domestic flights must clear customs in Terminal 2 and then re-check in for their Southwest connection in the same terminal, which is straightforward from a checkpoint perspective. Passengers connecting from Heathrow to Delta, United, American or Alaska departures in Terminal 1 must exit Terminal 2 entirely, board the inter-terminal shuttle and re-clear security at the appropriate Terminal 1 checkpoint, which makes the 3-hour international arrival buffer even more important for those itineraries.

Beyond the British Airways launch, the longer-term infrastructure picture at Lambert is defined by the planned consolidated single terminal. The airport is working toward a new 64-gate terminal designed by HOK on the Terminal 1 site, with design work approximately 30 percent complete as of April 2026 and project completion targeted for 2032. Concourse A in Terminal 1 is expected to close in August 2027 as the first construction phase begins. Current operations are not disrupted, but passengers should monitor flystl.com for any announcements as planning progresses. The project does not affect the checkpoints passengers will use through at least mid-2027.

St. Louis Lambert Airport Security Wait Times by Checkpoint

St. Louis Lambert Airport's three concourses are accessible from three separate security checkpoints spread across two terminal buildings. Your checkpoint is determined by your concourse, which is determined by your airline. There is no shared airside area between any of the three checkpoints. Within Terminal 1, Concourses A and C are at opposite ends of the building with no airside passage between them, so passengers must exit security and re-enter at the correct checkpoint if changing concourses. Terminal 2 has a single checkpoint serving all gates in Concourse E. Gate walks within each concourse once past security are straightforward: Concourse A spans roughly 5 to 8 minutes to the furthest gate, Concourse C spans 8 to 12 minutes to the furthest gate, and Concourse E spans 8 to 14 minutes from end to end.

Concourse A Checkpoint Security (Delta, United, Air Canada)

Concourse C Checkpoint Security (American Airlines, Alaska, Frontier)

Concourse E Checkpoint Security (Southwest, Lufthansa, British Airways)

St. Louis Lambert Airport Security Peak Hours and Best Times to Fly

The two busiest windows at St. Louis Lambert Airport security are 05:30 to 08:30 and 16:00 to 19:00. Southwest Airlines accounts for around 60 percent of all STL passenger traffic and banks morning departures heavily from Concourse E in Terminal 2, generating concentrated queue pressure at the Concourse E checkpoint from around 05:30 on every day of the week. The Concourse A and Concourse C checkpoints in Terminal 1 build during the same morning window as Delta, United, American and Alaska morning departures bank. Fridays, Mondays and Sundays carry the heaviest load across all three checkpoints. Saturday midday can also see pronounced queues at the Concourse E checkpoint, where leisure-heavy Southwest traffic peaks. Holiday travel periods add significantly to all baselines: Thanksgiving week, the Christmas and New Year period, Memorial Day weekend and Labor Day weekend generate the longest queues of the year across all checkpoints at Lambert.

The quietest windows at St. Louis Lambert Airport are 09:00 to 15:00 on weekdays and after 20:00 on any day. A Tuesday or Wednesday midday departure during a non-holiday period is the most relaxed combination available at STL, particularly at the Concourse A checkpoint, which carries the lightest volume of the three. The very early window from 04:00 to 05:30 is also quiet but builds sharply once Southwest morning operations ramp up from Terminal 2.

St. Louis Lambert Airport Priority Security: TSA PreCheck and CLEAR

Priority security at St. Louis Lambert Airport runs through two main programmes: TSA PreCheck and CLEAR. There is no terminal-specific paid priority pass at STL. Business class and first class ticket holders who are not enrolled in either programme queue in the standard lane alongside all other passengers. Delta Sky Priority, American AAdvantage status and Southwest's A-List status all provide boarding benefits but do not include separate security lanes at STL beyond TSA programme lanes. The two main ways to move through Lambert security materially faster are TSA PreCheck and CLEAR.

Recommended Arrival Times at St. Louis Lambert Airport

The TSA and St. Louis Lambert Airport both recommend arriving at least 2 hours before domestic flights and at least 3 hours before international flights. At STL, the 2-hour domestic recommendation accounts for ground transport to Lambert, check-in or bag drop, security and the gate walk to your concourse. STL is accessible by MetroLink Red Line from downtown St. Louis in approximately 25 minutes to Terminal 1 (exit 1, east end of ticketing) or Terminal 2 (exit 12, through the parking garage). For travelers arriving by road, Lambert International Boulevard off I-70 (Exit 238A) feeds both terminals, but the shared approach road can back up during departure peaks on Fridays, Mondays and busy holiday weekends as both terminals use the same boulevard.

When Should I Leave for St. Louis Lambert Airport? Calculator

Enter your flight details below to get a recommended time to be inside the STL terminal. The calculator factors in the typical St. Louis Lambert Airport security wait at your departure hour, gate walk time within your concourse, bag drop time and a safety buffer.

Tips to Beat St. Louis Lambert Airport Security Queues

A few practical decisions can significantly reduce your time in the STL security queue regardless of which checkpoint you are using.

• Confirm your terminal and concourse before leaving home. This is the most important tip at Lambert. Southwest, Lufthansa and British Airways use Concourse E in Terminal 2. Delta, United and Air Canada use Concourse A in Terminal 1. American Airlines, Alaska and Frontier use Concourse C in Terminal 1. Arriving at the wrong terminal costs 15 to 25 minutes to exit, shuttle and re-screen. Arriving at the wrong concourse within Terminal 1 also costs you 10 to 15 minutes, as Concourses A and C are not connected airside.
• Enroll in TSA PreCheck before your next STL flight. At $78 for five years, PreCheck is the most cost-effective security upgrade at Lambert. Any passenger who flies more than twice a year and does not hold PreCheck is leaving significant time on the table, particularly during the 05:30 to 08:30 Southwest morning peak when standard lane waits at the Concourse E checkpoint routinely reach 25 to 35 minutes. The on-site enrollment center at STL has closed, but CLEAR pods at all three checkpoints offer enrollment assistance, and you can apply online at tsaprecheck.com.
• Use CLEAR to eliminate document check delays at all three STL checkpoints. CLEAR is confirmed at the Concourse A, Concourse C and Concourse E checkpoints. Combined with PreCheck, it reduces a peak-period security experience to under 8 minutes in most cases. Delta SkyMiles members receive a discounted CLEAR membership rate.
• Check the flystl.com homepage before you leave. Lambert publishes real-time checkpoint wait times at flystl.com. Checking 30 to 60 minutes before you plan to leave allows you to adjust your departure if the morning Southwest peak is running longer than usual or if holiday traffic has built unexpectedly across all three checkpoints.
• Arrive by MetroLink to remove road uncertainty. The MetroLink Red Line connects Terminal 1 (exit 1) and Terminal 2 (exit 12, through the garage) to downtown St. Louis in approximately 25 minutes. Rail is particularly valuable on Fridays and Mondays when Lambert International Boulevard and I-70 traffic adds unpredictability to drive times from the city and suburbs.
• Avoid the 05:30 to 07:30 window at the Concourse E checkpoint if you do not hold PreCheck. The Southwest morning bank generates the most acute standard lane queues of any window at STL. If your Southwest flight departs at 07:00 and you do not hold TSA PreCheck, arriving at the Concourse E checkpoint by 05:00 puts you ahead of the main wave. After that window the standard lane at Concourse E fills quickly and stays full through mid-morning.
• Pack liquids in your checked bag where possible. The 3-1-1 rule still applies at all three STL checkpoints even on CT-equipped lanes. Removing the liquid step speeds up the conveyor and reduces the chance of your bag being pulled for secondary screening during busy periods.
• Use mobile boarding passes and check in online. Southwest allows mobile check-in beginning 24 hours before departure; checking in at exactly T-24 hours is important for Southwest as it determines your boarding group position. Delta, United, American and Alaska also support mobile boarding passes via their apps. All of these reduce landside processing time before the security queue.
• If connecting between airlines at STL, build in the inter-terminal buffer. Travelers connecting from a Terminal 1 arrival to a Terminal 2 Southwest departure or vice versa must exit security, board the free shuttle and re-clear. Allow at least 45 minutes from gate to gate for this transfer during off-peak periods and 60 minutes or more during the morning and afternoon peaks. The shuttle runs 24 hours and departs approximately every 8 to 15 minutes.

St. Louis Lambert Airport Layout and Concourse Overview

St. Louis Lambert International Airport (STL/KSTL) is located approximately 14 miles northwest of downtown St. Louis in unincorporated St. Louis County, Missouri, between the communities of Berkeley and Bridgeton. It is the largest and busiest airport in Missouri, serving approximately 16 million passengers in 2024 and offering nonstop service to over 80 destinations in the United States, Canada, Mexico, the Caribbean and Europe. Southwest Airlines accounts for roughly 60 percent of total passenger traffic, making Lambert one of the carrier's most significant focus cities in the Midwest. The airport is named after Olympic medalist and prominent St. Louis aviator Albert Bond Lambert and is famous for its iconic 1956 terminal domed roof designed by architect Minoru Yamasaki, who also designed the original World Trade Center towers.

STL operates two separate terminal buildings: Terminal 1, the original Yamasaki-designed building with two concourses, and Terminal 2, a separate building at the southern end of the airport with one concourse. Terminal 1 contains Concourse A at its northwest end (15 gates, Delta Air Lines, United Airlines and Air Canada) and Concourse C at its southeast end (20 gates, American Airlines, Alaska Airlines and Frontier Airlines). The two concourses are not connected airside and each has its own security checkpoint on the lower arrivals level. Terminal 2 contains Concourse E (18 gates, Southwest Airlines, Lufthansa and British Airways). The two terminals are roughly one mile apart on Lambert International Boulevard and are connected by a free 24-hour inter-terminal shuttle bus operating every 8 to 15 minutes. There is no airside connection, train or walkway between the terminals. MetroLink Red Line serves both terminals independently. A long-term plan to consolidate both terminals into a single 64-gate building on the Terminal 1 site is under design by HOK, with construction expected to begin in 2027 and the new terminal targeted to open in 2032. For the full concourse layout, gate assignments and navigation guide, see our St. Louis Airport map and terminal guide.