Houston's George Bush Intercontinental Airport (IAH) is a large multi-terminal airport, and first-time visitors are often surprised by how spread out it is. Five terminals, two different trains, and a Terminal B construction project that changes where United Express passengers check in — knowing all of that before you leave home saves real stress. Our IAH airport shuttle serves IAH around the clock; this guide covers the terminal layout, how the transfers actually work, and where your ride meets you. Read more about Conroe to IAH shuttle.
IAH terminal basics
IAH has five terminals lettered A through E, linked airside by the Skyway train and landside by the underground Subway. Domestic and international carriers are spread across them, so your terminal depends on your airline, not your destination city. Read more about which Houston airport to choose. Always confirm the terminal on your boarding pass the night before — showing up at the wrong one means a landside ride to the right building, and that ride puts you back through security.
Every IAH terminal uses the same vertical stacking: arrivals and baggage claim on Level 1, check-in and departures on Level 2, and the Skyway platforms on Level 3. Learn that one pattern and the airport stops feeling random. Read more about Conroe to Houston distance. Land on Level 1, leave from Level 1, check in on Level 2.
Which airline uses which IAH terminal
Terminal assignments are set by the airlines, but the broad map is stable enough to plan around:
- Terminal A — domestic flights, including carriers such as American and Delta.
- Terminal B — United Express regional flights. During the Terminal B transformation project, B's check-in lobby, TSA checkpoint, and baggage claim are closed, so B passengers check in and clear security at Terminal C.
- Terminal C — United's main domestic terminal, handling the largest United domestic volume at IAH.
- Terminal D — international carriers, including Emirates and British Airways. Air France, KLM, and Lufthansa moved their check-in to Terminal E in March 2026.
- Terminal E — United's international operation, the expanded international check-in used by Air France, KLM, and Lufthansa, and the International Arrivals Hall where international passengers clear Customs & Immigration.
Gate and terminal assignments can change between booking and travel day, so treat the boarding pass and the airline app as the final word. Our IAH Terminal C guide goes deeper on the United side of the airport, including gates, clubs, and checkpoint timing.
Terminal transfers: the Skyway and the Subway
IAH runs two separate trains, and mixing them up is the most common connection mistake at this airport.
The Skyway is the elevated people mover inside security, on Level 3. It connects all five terminals, trains arrive about every two minutes, and you do not re-clear security to use it. If you are connecting from a United Express flight at a B gate to a mainline departure at C — or the reverse — you stay airside and ride the Skyway. The trip is a couple of minutes; the walk to and from the platform is what eats the time.
The Subway is the underground train on the public side, running at the ticketing and baggage levels. It links the terminals and the airport Marriott, and it opened with the airport in 1981, which is why it feels older than the Skyway. Use it when you are landside anyway — meeting someone, switching terminals after a curb drop-off, or getting to the hotel. Do not use it mid-connection: taking it puts you back through a TSA checkpoint, and at Terminal C that checkpoint is one of the busiest in the building.
Both trains are free and frequent, but neither is instant during peak banks. If your connection is tight, add the platform walk and any checkpoint wait before you decide it is comfortable.
The Terminal B detour, for United Express passengers
This is the quirk that catches regional flyers. While the Terminal B transformation project runs, Terminal B's check-in lobby, TSA checkpoint, and baggage claim are closed. Every Terminal B passenger checks in and clears security at Terminal C, then rides the Skyway to the open B gates.
Practically, that means two things. If someone is dropping you off for a United Express regional flight, the drop is at Terminal C, not B. And if you are connecting through a B gate, stay airside and use the Skyway rather than walking out to the curb.
Getting to IAH by car
IAH is reached off JFK Boulevard — from the Sam Houston Tollway (Beltway 8) or the Hardy Toll Road — or off Will Clayton Parkway from US-59/I-69. Once inside the airport loop, terminals run A through E roughly west to east, and C is the middle stop of the domestic three.
Two Houston-specific notes. The upper-level roadway backs up during the 4 to 7 p.m. arrival banks, so a departure drop in that window needs extra margin. And while Terminal B's construction is active, the Terminal C curbside is the smarter drop for United passengers of every stripe. Each terminal has a designated curbside lane on both the arrival and departure levels, which makes a quick drop-off simple — you pull in, hand off the bags, and go.
Meeting your shuttle at IAH
After baggage claim, follow the Ground Transportation signs to the signed pickup areas outside each terminal. At Terminal C, pre-arranged ground transportation — including your Texas Shuttle — meets curbside on the arrivals level, outside Door C-102 on the north side.
A few habits make the curb work:
- Collect your bags first. Pickup timing is built around baggage claim, so there is no gain in standing at the curb without luggage.
- Wait inside if Houston weather is ugly. Gulf Coast summers are steamy and storm cells pop up fast — stay in the air-conditioning until your driver texts that the vehicle is at the curb.
- Keep your phone handy and your confirmation open. Your driver confirms the exact meeting point when you book, and the terminal name matters more than the address.
Driving yourself means terminal parking fees plus a garage walk, and parking at either Houston airport commonly runs $15 to $30 per day. A reserved IAH airport shuttle pickup skips that entirely and puts you curbside-to-door.
Pickup timing built around baggage claim
Our default pickup windows exist because the walk from gate to curb is not a fixed number:
- Domestic arrival: we normally pick you up 30 minutes after your plane lands — enough time to deplane and claim bags.
- International arrival: 45 minutes, because immigration, baggage, and customs all sit between the gate and the curb.
- No checked bags: 15 minutes after landing.
- Late flight: your pickup shifts automatically with the flight. You do not need to call and rebook.
How early to arrive for an IAH departure
IAH's guidance is 3 hours before an international flight and 2 hours before a domestic one. Those numbers assume you are inside the terminal with your bags, not pulling into the curb. The tightest check-in and checkpoint windows are 6 to 9 a.m. and 4 to 7 p.m.
Terminal C deserves its own warning: it handles the largest United domestic volume at IAH and, during the B rebuild, its checkpoints shoulder Terminal B's passengers too. Terminal C lines are longest at 6 a.m. If you are flying out of C on an early bank, arriving at the front edge of the 2-hour window is not padding — it is the realistic plan.
Mistakes that cost the most time at IAH
- Assuming your airline's "usual" terminal. Confirm it on the boarding pass; assignments move, and Terminal B's project moved an entire airline's check-in to C.
- Using the Subway on a connection. It is landside. You will re-clear security.
- Booking a tight connection without counting the walk. Gate C1 to the far end near C45 is a solid 10 to 15 minute walk; add the Skyway ride if you are changing terminals.
- Texting the driver at wheels-down. Text when you have bags in hand.
- Ignoring gate changes. Check the flight displays or the airline app after you land, not just at booking.
FAQ
How many terminals does IAH have?
Five, lettered A through E, connected by the Skyway train airside and the underground Subway landside.
Which terminal is United at IAH?
United's mainline domestic flights use Terminal C and United's international operation uses Terminal E. United Express regional flights use Terminal B gates, but during the Terminal B rebuild those passengers check in and clear security at Terminal C.
How do I get between terminals at IAH?
Inside security, ride the Skyway on Level 3; trains arrive about every two minutes and you do not re-clear security. Outside security, use the Subway at the ticketing and baggage levels, which also connects to the airport Marriott.
Do I have to re-clear security to change terminals at IAH?
Not if you stay airside on the Skyway. Any landside move — the Subway, walking outside, or returning to a curb — means going back through a TSA checkpoint.
Where does my shuttle pick me up at IAH?
In the signed ground-transportation pickup areas outside each terminal. At Terminal C, pre-arranged pickups meet outside Door C-102 on the north side of the arrivals level.
How early should I arrive at IAH?
Three hours before an international flight and two hours before a domestic one, counted from inside the terminal. Morning and late-afternoon peaks are the busiest windows.
