Key Points

• Southwest signed a new interline agreement with Air Premia, South Korea's hybrid carrier, allowing single-ticket bookings between the two airlines.
• The partnership connects through Los Angeles, San Francisco, and Honolulu, opening up Southwest's domestic network to travelers arriving from Korea.
• There's no mileage earning or elite benefit crossover yet, so treat this as a booking convenience rather than a points strategy.

Southwest just added its ninth international partner in the past couple of years, and this one comes with a twist. The new interline agreement with Air Premia, South Korea's fast-growing hybrid carrier, lets travelers book a single ticket that spans both airlines and check their bags straight through, at least in one direction.

If you've been eyeing a trip that combines Korea with a Southwest-served city like Nashville, Denver, or Houston, this partnership is worth understanding before you book. Here's what actually changed and what it means for your next trip.

What Happened

Southwest and Air Premia announced an interline agreement that took effect for ticket sales starting July 8, 2026. This marks the first time a Korean airline has entered into such an agreement with the largest domestic carrier in the U.S.

An interline agreement is a step below a full codeshare partnership. It means there are no opportunities for reciprocal loyalty benefits or earning and redeeming miles across the two airlines, since that level of integration only happens with a codeshare. What you do get is the ability to purchase one itinerary covering both carriers and have your checked bags follow you to your final destination, at least on one leg of the trip.

Southwest and Air Premia overlap at three West Coast gateways: Los Angeles, San Francisco, and Honolulu. That means travelers flying in from Korea can connect through one of these three airports to reach Southwest cities that Air Premia and other Korean carriers don't serve directly, including Las Vegas, Chicago Midway, Houston Hobby, Phoenix, Denver, Portland, and Nashville. You can check Southwest's route map and current fares directly to see which connections work best for your trip.

Air Premia itself is still a relatively young airline. It launched its first international route back in July 2022 and has built a reputation for flying long-haul routes that budget carriers typically skip, while keeping fares below what full-service Korean airlines charge. It currently flies to Los Angeles, San Francisco, New York, Washington D.C., Honolulu, and Tokyo, so this new tie-up with Southwest gives it meaningfully deeper access to the U.S. than it could offer flying solo.

Why This Matters for Your Travel Planning

The baggage rule is the detail most travelers will trip over if they don't read the fine print first. Because U.S. entry regulations require anyone arriving from South Korea and connecting onward to claim their checked bags and clear customs at their first port of entry, inbound Air Premia passengers connecting to a Southwest flight will need to grab their bags at LAX, SFO, or HNL and recheck them before continuing on. Budget extra connection time for this step, especially if you're already cutting it close between flights.

Going the other direction is more convenient. If you're starting your trip on a domestic Southwest flight and connecting onto an Air Premia international flight, you can check your bags straight through to Korea or wherever your final stop is beyond it. That makes Southwest a genuinely useful first leg for travelers in cities without direct Korea service who want to avoid re-checking bags mid-trip.

It's also worth being clear about what this partnership isn't. This is not a way to earn Rapid Rewards points on your Air Premia flight, and it won't help you toward Companion Pass or A-List status either. If you're building a Southwest Companion Pass strategy, this deal doesn't move the needle, since none of Southwest's current interline agreements extends past interline status, meaning mileage earning and elite benefits aren't part of the deal with any of these carriers yet. For the fastest path to Companion Pass, our breakdown of three clever ways to earn it in 2025 is still the better resource.

Air Premia isn't new to this kind of arrangement either. The carrier already has interline deals with Korean Air, Thai Airways, and T'way Air, so linking up with Southwest fits a pattern of stitching together connections it can't yet fly nonstop.

What You Should Do

If you're planning a trip between Korea and a Southwest city, here's how to actually use this partnership:

• Book through a travel agency or an online channel that supports interline itineraries rather than booking each leg separately, since that's what gets you the checked-bag benefit and a single confirmation to manage.
• Build in a longer connection window at LAX, SFO, or HNL if you're arriving from Korea, since you'll need time to clear customs, collect bags, and recheck them for your Southwest flight.
• Don't expect Rapid Rewards credit for the Air Premia portion. If earning miles on the international leg matters to you, it's still worth comparing what you'd get by crediting that flight to a partner program Air Premia already has in place.
• Watch for this relationship to deepen. Southwest has been adding international partners at a steady pace, and it wouldn't be surprising if some of these relationships eventually grow into something closer to a full codeshare. If that happens with Air Premia, mileage earning could become part of the equation down the line.

Southwest's partner list has grown quickly, now including China Airlines, Condor, EVA Air, Icelandair, Philippine Airlines, Singapore Airlines, Turkish Airlines, ANA, and now Air Premia. For travelers who've written off Southwest for international connections in the past, it's worth another look, particularly if your route runs through one of the West Coast hub cities.

If you're a frequent Southwest flyer wondering how this fits into your broader points strategy, our guide to Southwest Airlines credit cards breaks down which options still make sense for earning toward future domestic and partner-connected trips. The Southwest Rapid Rewards Priority Credit Card is worth a look if you fly Southwest regularly, since it earns 3x points per dollar on Southwest purchases along with a handful of travel-focused perks that help offset the annual fee.

FAQ

Can I earn Rapid Rewards points on an Air Premia flight?

No. This is an interline agreement, not a codeshare or loyalty partnership, so there's currently no way to earn or redeem Southwest points on Air Premia flights, or vice versa.

Which airports connect Southwest and Air Premia flights?

Los Angeles (LAX), San Francisco (SFO), and Honolulu (HNL) are the three overlap points where you can connect between the two airlines on a single ticket.

Do I need to recheck my bags when connecting from Air Premia to Southwest?

Yes, if you're arriving from South Korea. U.S. customs rules require you to claim your bags and clear customs at your first port of entry, then recheck them for your connecting Southwest flight.

Will this partnership eventually include mile earning?

There's no confirmed timeline, but Southwest has been steadily expanding its network of interline partners, and some industry watchers expect at least a few of these relationships to deepen over time.

Final Thoughts

This partnership won't change your points strategy, but it does make Southwest a more practical option if your travel plans involve South Korea. The bag-recheck requirement on inbound flights is the one detail worth building into your connection times, and the through-check benefit heading toward Korea is a genuine convenience for anyone starting their trip on a Southwest flight.

Keep an eye on how this relationship evolves. Airlines rarely stop at interline status once the operational kinks are worked out, and Southwest's recent pace of partner additions suggests more international access is likely on the way.

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