Which Terminal Is Southwest at Boston Logan? Terminal B — and the Checkpoint Matters More

The terminal is the easy part. What actually catches people out at Logan is that Terminal B is a wide U-shape wrapped around a parking garage, with two separate security checkpoints — and going through the wrong one can mean a long backtrack or a full re-screen.

Terminal B is effectively two buildings

Terminal B has north and south sides joined by a central hall, each with its own ticketing area and its own TSA checkpoint. Southwest check-in sits on one side — signposted from the curb, but not obvious if you're dropped at the first Terminal B door you see.

Here's the honest part: published guides disagree about which checkpoint serves which Southwest gates. Some describe the checkpoints as east and west, others as north and south, and gate assignments shift by season and schedule. Southwest is a common trap here — check-in can feel like it's on one side while the departure gate is on the other.

So use the rule that always works: go by your gate number, not by which counters you see first. Check the gate on your boarding pass or the airport screens before you get out of the car, and enter on the side that serves it. If you're checking a bag you'll need Southwest's counters regardless, so allow the extra walk.

One structural quirk worth knowing: a small pocket of low-numbered B gates can't be reached from the main secure concourse. If your boarding pass shows one of those, the wrong checkpoint means exiting and re-screening.

Airlines in each Logan terminal

Terminal	Airlines
A	Delta, Delta Connection and partners
B	Southwest, American, United, Alaska, Air Canada, Boutique Air
C	JetBlue (primary base), plus Aer Lingus, Etihad, TAP Air Portugal, Cape Air
E	International arrivals and most foreign carriers

A note on sourcing: many third-party Logan guides still list Spirit Airlines in Terminal B. Spirit ceased operations in May 2026, so a page showing Spirit hasn't been updated since — treat everything else on it with the same suspicion. Massport publishes the authoritative airline-to-terminal list.

Southwest arrivals at Logan

Southwest arrives into Terminal B. Baggage claim is on Level 1, one floor below departures, and ground transport works from the arrivals curb:

• Silver Line SL1 runs directly from every terminal curb to South Station, with a free transfer to the Red Line. It is free in the direction leaving the airport — no ticket, no tap. You pay only on the way back in. At rush hour it's often the fastest route downtown, and the buses have proper luggage space.
• Blue Line connects at Airport station, reached by the free Massport shuttle (Route 88) from every terminal. Airport station is not walkable to the terminals.
• Logan Express coaches serve Braintree, Framingham, Peabody, Woburn and Back Bay.
• Water shuttle from the Logan Ferry Terminal to Long Wharf, Lovejoy Wharf, Hingham and Hull, reached by the free Route 66 shuttle.
• Rideshare and limousine pickup is on Level 2 of the terminal parking garage, across the pedestrian walkways — not at the arrivals curb. Logan moves these zones periodically, so follow current signage.

Connecting to or from Southwest at Logan

Southwest doesn't interline the way legacy carriers do. If your Southwest flight is one leg of a journey on another airline, you almost certainly have two separate bookings — which means:

• Bags will not transfer. Collect them at baggage claim and re-check with the next carrier.
• You exit security and re-clear it.
• A missed connection isn't the airline's problem. Leave a far bigger buffer than you would on a single ticket.

Logan does have a post-security walkway from the far end of Terminal B to Terminal C, and Terminal C connects post-security to Terminal E. Useful for single-ticket itineraries. It doesn't help across separate bookings, since you're going landside for bags anyway.

Terminal A has no post-security connection to the rest of the airport — a connector is planned but not expected until around 2028. A Southwest-to-Delta transfer means going landside and re-clearing security. Budget for it.

Timing at Terminal B

• Domestic, no checked bag: arrive two hours before departure. Terminal B is one of Logan's busiest, and because the checkpoints don't share queues, a short line on one side tells you nothing about the other.
• With a checked bag: add 30 minutes, and check Southwest's published bag-drop cutoff.
• Boarding: Southwest boards by numbered position rather than assigned seats. Position is set by check-in time or fare, so check in as close to 24 hours before departure as you can. Be at the gate for the start of boarding — the difference between an A and a C position is the difference between an overhead bin and gate-checking your carry-on.
• TSA PreCheck and CLEAR are available in Terminal B. Which lanes are open varies by checkpoint and time of day.

Terminal B roadway work is underway through 2026, separating bus traffic from passenger vehicles. Expect the drop-off pattern to differ from your last visit.

Getting to Terminal B

Driving: follow signs for Terminal B; it has its own central garage.

Blue Line: to Airport station, then the free Massport shuttle. Note that the T is only free in the outbound direction from Logan — heading to the airport you'll need a CharlieCard, CharlieTicket or contactless tap.

Silver Line SL1: stops at every terminal curb. From South Station this is the simplest route in.

Logan Express: stops at each terminal on its loop.