Alaska is in a pitched battle with Delta over their home market of Seattle.

And — which believes its mileage program is a real advantage in this battle — wants you to engage with their frequent flyer program, so as long as one passenger in a reservation is crediting flight miles to the Mileage Plan program each passenger’s first checked bag will be free in January.

Throughout the month of January Alaska Airlines Mileage Plan members can check one bag free.* The airline is waiving its standard $25 bag fee to encourage new and existing members to experience the benefits of Alaska’s award-winning frequent flier program.

Alaska is competing by offering more to its customers which I absolutely love.

Checked bag fees are one of the pain points of flying that irritate passengers most.

And Alaska is even good with checked bags, having offered a baggage delivery guarantee since 2009. They currently offer 2500 miles or a $25 discount on a future flight if they don’t deliver checked bags within 20 minutes. (Pro-tip: the miles are worth more.)

Alaska Mileage Plan miles are some of the most valuable of any airline.

Alaska believes that continuing to award miles based on distance flown rather than revenue will be a competitive advantage against Delta. By adding on more bonuses for elites and premium customers they’ve run the numbers and see 95% of members coming out the same or better with their system compared to a revenue-based one.

Now in addition to a better mileage offering, they’re offering better value for passengers checking a bag. And what does Delta offer? Perhaps not more than Venus envy.

Will it Matter?

Free checked bags alone don’t make a carrier the clear choice in a market.

But checked bags are a customer pain point, it’s a huge area of investment for co-brand credit card issuers (interestingly, free checked bags are not a benefit of the Alaska Airlines card from Bank of America).

And Alaska is using this as a short term play to highlight their mileage program, which they believe is a differentiator. So at some margin it should matter.

Here Are the Offer Terms:

Terms and conditions for the free checked bag: Mileage Plan members and companions traveling on the same reservation will receive their first checked bag free on qualifying reservations when they check-in for their flight or at the airport. The promotion is valid for flights flown between 12:01 a.m., Jan. 1 through 11:59 p.m., Jan. 31. At least one valid and active Mileage Plan number must be in the reservation at the time of check-in, and flight miles must be credited to Mileage Plan to qualify. Offer may not be applied retroactively, and no refunds will be issued. Not applicable for travelers who already receive one or more free checked bags. Travel is valid on flights marketed by Alaska Airlines and operated by Alaska Airlines, Horizon Air, SkyWest or PenAir between January 1, 2015, and January 31, 2015. Free first checked bag must weigh 50 pounds or less and have a maximum dimension of 62 linear inches (length + height + width) to avoid additional charges.

Update: I’ve clarified the “flight miles must be credited to Mileage Plan to qualify.” A Mileage Plan number must be in the reservation – that’s all – the ticket doesn’t have to be mileage-earning (in other words, award flights are eligible for the free bag).

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