Millions of Americans — 30 million, to be exact — will be taking to the skies over the Thanksgiving holiday period, which began Nov. 17 and stretches through Nov. 28.

The Sunday following Thanksgiving is expected to mark the busiest day in the stretch, with a projected 2.9 million passengers passing through TSA. The Tuesday and Wednesday before Thanksgiving are also expected to be busy, with 2.6 million and 2.7 million passengers respectively, the agency said.

Sunday’s figure would surpass the country’s current single-day travel record set on June 30, when TSA screened nearly 2.9 million passengers, the agency said.

At Sea-Tac, passenger volume is expected to surpass 2019 levels, said airport spokesperson Perry Cooper. Volume at the airport is expected to be about 11%, higher than last year.

Mirroring national travel projections, passenger volume at Sea-Tac is projected to peak Sunday with a total of 158,000 departing, arriving and connecting passengers. The Wednesday before and the Monday after Thanksgiving are also expected to be particularly busy, according to airport officials.

More than one-third of Sea-Tac’s daily passenger volume arrives at the airport before 9 a.m., “so those with early flights should take the most care,” airport officials said. The next waves of high travel volume are 2-5 p.m. and 9-11 p.m.

Passengers may also notice something new at the airport: Sea-Tac’s “Gateway Project” is currently underway with construction projects from curb to gate.

If you haven’t been to the airport in a while, brace yourself for barricaded entrances, scaffolding, walled-off areas and tight quarters — especially in the Alaska Airlines ticketing section and in the baggage claim areas.

The Port of Seattle’s $546 million upgrade project, in partnership with Alaska Airlines, will reconfigure the 40-year-old terminal north end ticketing area, expand the security checkpoint and create an updated, light-filled and open terminal space with new technology and building standards.

The construction, which is being completed in two phases through 2025, is expected to affect ticketing and baggage claims across the airport.

As passengers travel through these areas, “it’s going to look completely different,” said Lea Kautzman, managing director of Sea-Tac guest services.

The airport recommends Alaska Airlines passengers check in for their flight before they get to the airport, and if they don’t have a bag, go straight to security and skip the lobby.

In general, the airport also recommends arriving at least two hours before domestic travel and three hours before international travel, “and we really mean that,” Kautzman said. “So get here early and be prepared.”

Travelers should take factor in how long it will take them to park or arrive, whether by using off-site parking and a shuttle, parking in the garage, getting dropped off or taking light rail.

Here are some other recommendations from the Port of Seattle to make your airport travel more predictable and efficient this holiday season.

Before you arrive

To stay up to date on flight delays and cancellations, visit portseattle.org/sea-tac/flight-status. Passengers can also check daily airport delays and cancellations on tracking website FlightAware.

For weather conditions at Sea-Tac, the National Weather Service, which has a station at the airport, shares the latest conditions and forecast on its website.

Drivers headed to the airport curb should expect “serious congestion” during peak periods, the airport said. It encourages the use of public transportation, parking, a taxi, app-based rideshare or shuttles.

If driving to the curb is your only option, consider downloading the Washington State Department of Transportation app, available on iOS and Android platforms. The app will show you the best route to take and updates on traffic conditions on all Seattle- and Tacoma-area highways. The app also provides ferry schedules and tolls, mountain pass information and construction updates.

Once you arrive at the airport, Sea-Tac recommends ignoring the departures and arrivals signs. Instead, use the fastest-moving lane and an escalator or elevator inside the airport to reach the right level.

You can also watch the drive cameras on the airport’s website to see how busy Upper Departures Drive and Lower Arrivals Drive are as you plan your drop-off and pick up.

If you haven’t thought about parking, you’re already out of luck. Pre-booked general parking at the airport was sold out through the holiday period as of Friday morning. Pre-booking does not reserve a spot but rather allows travelers to prepay for a spot and often get a savings deal compared with the drive-up price. The airport does not offer parking reservations.

If you are considering parking, the airport recommends planning an extra 45 to 60 minutes to find a spot. There’s an automated parking guidance system that will help you find a spot with lighting that indicates available stalls.

Saving time at security

SEA Spot Saver is an appointment program available for all Sea-Tac passengers for security screening. Just like CLEAR, Global Entry and TSA Precheck, the SEA Spot Saver has its own dedicated lane at security checkpoints, so you can skip the general boarding lines.

To use SEA Spot Saver, the airport recommends reserving a time up to 72 hours before your flight because spots are limited. Appointment times are available from one to four hours before departure. If you’re traveling with a group, up to 10 passengers can be booked under one appointment.

Passengers can also sign up at the airport by scanning a QR code on SEA Spot Saver signs throughout the airport.

Then, all you need to do is walk up at your appointment time at your assigned checkpoint to skip the security line. Each appointment has a grace period of 15 minutes.

SEA Spot Saver can be used between 5 a.m. and 10 p.m. at checkpoints 2, 3 and 5, which lead to all gates.

The MyTSA app, available on iOS and Android platforms, can help passengers figure out which items they can bring through security and get 24-hour information on how to prepare for and get through the security checkpoint quickly. Travelers can request live assistance from TSA, verify checkpoint wait times at the airport and sign up for TSA Precheck through the app.

MyTSA also contains daily tips for getting through security, packing and traveling with children.

At the airport

The FlySEA app is available on iOS and Android platforms. The app allows passengers to:

• Check wait times at TSA security checkpoints.

• Search for places in the airport like airline clubs and lounges, the massage bar, restaurants, the meditation room and more.

• Find arriving and departing flights, verify boarding gates and check if flights are on time.

• Capture a photo of your car and the floor, row and space number if you parked in the airport garage.

• Calculate your walk time to locations in the airport such as the closest coffee bar or your gate.

• Get up-to-the-minute updates on your flight and any changes.

Passengers can text “YES1” to 27829 to receive regular updates and alerts on Sea-Tac operations and services. Passengers can also find updates on Sea-Tac’s Facebook page and the social media platform X.

To avoid awkwardly maneuvering luggage through long lines at airport restaurants, try Order SEA. With this mobile ordering service, passengers can order food for pickup from 20 airport restaurants such as McDonald’s, Hachi-Ko, Ballard Brew Hall, Rel’Lish Burger Lounge and Pei Wei.

Passengers can place orders at ordersea.org or on the FlySEA App, pay from a phone and choose a pickup time. Delivery for OrderSEA is unavailable, but the airport is working on returning this feature.

If you’re looking for a lounge to relax in, Lounge Buddy provides guides and reviews of all Sea-Tac’s airport and airline lounges. The app, which is available on iOS and Android platforms, will show which lounges passengers have access to as well as their operating hours and amenities.