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How early should I get to IAH?

George Bush Intercontinental Airport, Houston, TX · Checked Oct 14, 2026

The short answer

IAH doesn't publish a single rule. Most airlines ask for 2 hours domestic and 3 hours international.

Those are blanket rules. Your real number depends on your terminal, the time of day, traffic from your door, and whether you have PreCheck or a bag. Leave By works out your exact leave time.

Security lines at IAH

Houston Airports shows live checkpoint waits online but no typical figures. During the Feb-Apr 2026 federal shutdown it warned of longer-than-normal waits and said PreCheck and CLEAR availability could change day to day. In TSA's hourly screening counts for Mar 15-21 and Sep 13-19, 2026, the heaviest screening was about 5-9am, with a second, smaller peak in mid-afternoon.

Busiest times: 5:00-9:00am, Around 3:00pm, Mondays, Thursdays, Fridays and Sundays are busier; Tuesdays, Wednesdays and Saturdays typically lighter (Houston Airports).

Nationally, TSA checkpoints are busiest from 5 to 7 AM local time. See TSA's hourly numbers and the busiest days to fly.

TSA PreCheck: PreCheck hours differ by checkpoint: Terminal A North 4:00am-6:00pm, Terminal C North 4:00am-10:00pm, Terminal E 4:00am-8:00pm. Terminal A South and C South list no PreCheck hours, Terminal B's checkpoint is closed, and Terminal D listed standard screening only in April 2026. Houston Airports says PreCheck and CLEAR availability can vary day to day with staffing.

CLEAR: Available at this airport (see terminals below for which checkpoints).

Touchless ID: IAH appears on an April 2026 list of the 65 airports offering TSA PreCheck Touchless ID. Which airlines and checkpoints support it at IAH was not confirmed from an official source.

Terminals and checkpoints

Terminal A

American Airlines

Terminal A NorthPreCheckCLEARCheckpoint 3:30am-7:30pm; TSA PreCheck 4:00am-6:00pm; CLEAR daily 4:00am-6:00pm
Terminal A SouthCheckpoint 3:30am-12:00am; PreCheck hours not listed
  • American Airlines passengers are picked up on the Terminal A south side (Door A-115) per the airport's pickup page
  • Ride-app pickup is at Door A-114 (west side), Arrivals level

Terminal B (United; under reconstruction)

United

Terminal B checkpointPreCheckCLEARListed as closed. While the Terminal B lobby is closed, Terminal B passengers check in, drop bags and clear TSA at Terminal C, then ride the Skyway to Terminal B.
  • The United Terminal B ticketing lobby has been closed since Jan 21, 2025. The airport says it stays closed until late 2026, and United's project site says it reopens in Fall 2026.
  • United gates B3-B31 remain in use
  • United runs an optional shuttle bus between Terminal B (gates 4-11), Terminal C (gates 30-45) and Terminal E (gates 1-10) as an alternative to the Skyway
  • Terminal B South ride-app passengers should take the Skyway to Terminal A or C for pickup

Terminal C

United

Terminal C NorthPreCheckCLEARCheckpoint and TSA PreCheck 4:00am-10:00pm; CLEAR Sun-Fri 4:00am-7:00pm, Sat 4:00am-6:00pm. Also screens Terminal B passengers during the B lobby closure.
Terminal C SouthCheckpoint 4:00am-7:30pm; PreCheck hours not listed
  • All United Terminal B check-in and bag drop currently happens here
  • METRO's 102 Bush IAH Express bus serves Terminal C

Terminal D (international, including the new Terminal D-West concourse)

Terminal D checkpointCLEARModified hours because only two airlines currently operate from the terminal: Sun, Mon, Wed and Fri 7:00-11:30am and 4:30-8:00pm; Tue, Thu and Sat 7:00am-8:00pm. An April 2026 airport update lists standard screening only. A separate table on the same page lists 4:00am-12:30am with PreCheck 5:00am-7:00pm, which conflicts.
  • Terminal D-West is the airport's new international concourse, next to the expanded Terminal E
  • International arrivals at Terminal D clear Customs in the Terminal E international arrivals hall
  • The two airlines currently operating from Terminal D were not named on the airport pages reviewed

Terminal E

United

Terminal E checkpointPreCheckCLEARCheckpoint 4:00am-12:00am; TSA PreCheck 4:00am-8:00pm. CLEAR is listed at Terminal E in the April 2026 airport update, and there is a post-security CLEAR enrollment center open daily 4:00am-6:00pm.
  • Customs and Immigration for international arrivals is in the Terminal E international arrivals hall
  • A TSA recheck area for international connections (opened August 2024) has a dedicated PreCheck lane past baggage claim
  • The METRO 500 IAH Downtown Direct bus stops at Terminal E, Level 2, Door E201

Between terminals: Inside security, the free Skyway train runs between Terminals A, C and D/E every two minutes (about 4 min 15 s from A to D/E). Outside security, the free Subway train links Terminals A, B, C, D/E and the Airport Marriott every three minutes, 3:15am-12:15am. The airport says the Subway lets you reach an open checkpoint in any terminal.

Terminals are connected after security, so you can walk between them without re-screening.

Getting to IAH

Rideshare and taxi: Drop off on the Departures level at all terminals; the airport enforces 'Active Loading', so curbside stops are for immediate unloading only. Ride-app pickups (Arrivals level): Terminal A west side Door A-114; Terminal C south side Doors C-103/C-104; Terminal E west side, Level 2, Zone 5. Terminal B South riders take the Skyway to A or C.

Transit: METRO 500 IAH Downtown Direct runs nonstop between Terminal E (Level 2, Door E201) and the George R. Brown Convention Center downtown: $4.50 one way, daily 5:30am-8pm, every 30 minutes. The METRO 102 Bush IAH Express serves Terminal C.

Driving and parking: Garage parking becomes reservation-only once garages reach 85% capacity, and ecopark2 (Will Clayton Pkwy) has been reservation-only since June 1, 2026. If you park in the A/B garage for a Terminal B flight, a United express shuttle takes you to your terminal.

Construction and changes in 2026

  • The United/Houston Airports Terminal B Transformation ($2.5B) is underway. The Terminal B ticketing lobby has been closed since Jan 21, 2025, with reopening expected in fall/late 2026. Until then, Terminal B flyers check in and clear security at Terminal C.
  • Road work near Terminals A and B ran from 10pm Mon Oct 12 to Fri Oct 16, 2026, with fewer lanes on southbound JFK Blvd near the Marriott as the airport prepares to open the new Terminal B. Drivers leaving A/B should allow extra time and follow detours toward Will Clayton Pkwy.
  • Terminal D's TSA checkpoint runs reduced, day-specific hours

IAH tips first-timers miss

  • Flying United from a B gate? Until the new Terminal B opens, you check in, drop bags and clear security at Terminal C, then ride the Skyway to Terminal B.
  • All terminals are linked airside by the Skyway, and landside by the Subway (3:15am-12:15am), so if your terminal's checkpoint is closed or backed up you can screen at another open one and ride to your gate
  • Check checkpoint hours before early or late flights: Terminal D's checkpoint keeps reduced hours (as late as 7am opening), and several PreCheck lanes close between 6pm and 10pm
  • Book parking ahead: garages switch to reservation-only at 85% full, and ecopark2 is reservation-only
  • Mondays, Thursdays, Fridays and Sundays are the busier days at IAH; Tuesdays, Wednesdays and Saturdays are typically lighter

Leaving for IAH?

Pick your flight and where you're starting. Leave By checks live traffic, security lines and your terminal, and tells you the minute to walk out the door.

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Questions travelers ask

How early should I get to Houston Bush airport (IAH)?

Houston Airports doesn't publish a fixed arrival time. It tells passengers to check live TSA wait times, stay in contact with their airline, and arrive early with extra time for screening, especially on busier Mondays, Thursdays, Fridays and Sundays.

Where do I check in for United flights from Terminal B at IAH?

At Terminal C. The Terminal B ticketing lobby has been closed since Jan 21, 2025 for United's rebuild, which is expected to finish in fall/late 2026. Terminal B passengers check in, drop bags and clear TSA at Terminal C, then take the Skyway to the B gates.

Can I move between terminals after security at IAH?

Yes. The free Skyway train connects Terminals A, C and D/E inside security every two minutes, about 4 minutes end to end. The Subway train connects all terminals before security.

Sources

Airport conditions change. Always follow your airline's check-in and bag-drop deadlines.

Other airport guides

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