Southwest just announced an unheard-of deal for its credit cards - you'll get the coveted Companion Pass simply by opening one

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Southwest Airlines

• When you open a new personal Southwest credit card, you can earn the best-ever sign-up bonus offered for the cards: 30,000 points and an unlimited Companion Pass, which is valid for travel through 2019.
• The Companion Pass lets you book a free ticket for a companion whenever you travel - all you'll have to pay is taxes and fees (which are typically as low as $5.60 each way).
• The offer applies to all three of Southwest's personal cards, but it ends on February 11.
• Our pick for the best Southwest card to open is the Southwest Rapid Rewards Priority Credit Card - however, read on to see which is best for you.

Southwest and Chase today announced that for a limited time, people who apply for any of their co-branded credit cards will be able to earn Southwest's coveted Companion Pass as a sign-up bonus.

The new sign-up bonus is effectively the best deal ever offered on any of Southwest's credit cards. In addition to the Companion Pass, which will be valid through 2019, new cardholders can also earn 30,000 Southwest Rapid Rewards points.

To earn the sign-up bonus, new cardholders must spend $4,000 on the card within the first three months of opening it. The bonus is only available until February 11.

The surprise promotion - coming just one day after a previous limited-time offer ended - represents what can arguably be described as the best-ever sign-up bonus offered by Southwest and Chase.

The Southwest Companion pass is often seen as the "holy grail" of travel for points-and-miles aficionados and self-described "travel hackers." When you earn the Companion Pass, you can select a designated friend or family member to travel with you for free for as long as the pass is valid.

Normally to earn the Companion Pass, one has to earn 110,000 qualifying points with Southwest within a calendar year. The pass will then be valid for the remainder of that calendar year, as well as the entirety of the following one.

Typically, you may be able to earn some of those qualifying points by opening a credit card and earning the normal sign-up bonus, but as Chase has added restrictions on who is eligible - for instance, you can't just open two consumer card at once, earn the bonuses, and use those points to qualify - it's become harder to earn unless you're a very frequent business traveler.

The ability to earn the Companion Pass purely as a sign-up bonus makes it significantly easy to acquire. Should new applicants hit the minimum spend requirement quickly, signing up for one credit card can equal 11 months of buy-one-get-one flights. Coupled with competitive fares on Southwest, the pass can be used for everything from longer vacations to easy, affordable weekends away. While taxes and fees are still charged on Companion tickets, these start at $5.60 for domestic flights, and rarely surpass $20-25.

In order to receive the bonus, you can't currently hold a personal Southwest credit card, and you can't have earned a sign-up bonus from a Southwest card in the past 24 months. If you currently hold a card, but earned the bonus from it longer than 24 months ago (or never earned the bonus), you may be able to close that, wait a week or so, and apply for a new card.

Southwest and Chase offer three personal credit cards. The Southwest Priority Card is the best option for most people because, even though it has the highest annual fee of the three cards - $149 - it offers annual credits and anniversary bonus points that are together worth at least $150, meaning the card pays for itself.

However, if you're dead set against an annual fee in the three-digit range, the other cards are compelling options - especially with the Companion Pass as a sign-up bonus.

Read on to learn more about the three personal Southwest cards.

Southwest Rapid Rewards Plus Credit Card

The Rapid Rewards Plus is the base-level of the three Southwest cards. However, just because it's a bit less featured than its bigger siblings doesn't mean it's a bad option.

The card earns 2x points per dollar spent on Southwest purchases, and 1x point per dollar on everything else. You'll also get 3,000 bonus points each year on your card membership anniversary.

That's essentially the gist of this card - there's not too much to it. There are, however, a couple of things worth noting.

It has a $69 annual fee that isn't waived the first year. Of course, the sign-up bonus - the Companion Pass for 2019 and 30,000 points - goes a long way toward making up for that, while the anniversary points help each year after.

All in all, while the Plus card has the lowest annual fee, it doesn't offer a ton of value after the first year. If you want to earn Southwest points on your credit card, but absolutely want to pay the lowest possible annual fee, then this card is probably the best option. However, if you're ok paying a higher annual fee, knowing that you'll get more value from the card than you'll pay in that fee, you're better off considering one of the other two.

Click here to learn more about the Southwest Plus card from Insider Picks' partner: The Points Guy.

Southwest Rapid Rewards Premier Credit Card

The Premier card is similar to the Plus, with a few enhancements.

The sign-up bonus is the same, but it offers 6,000 anniversary points each year instead of 3,000.

It also offers the ability to earn tier qualifying points, which count toward elite "A-list" status. You'll earn 1,500 tier points each time you spend $10,000 within a calendar year, up to $100,000 (or 15,000 tier points) per year.

Otherwise, the biggest appeal of the Premier over the Plus is that it doesn't have foreign transaction fees, while the Plus does - if you use your Plus abroad, you'll be charged an extra 3% on every purchase.

The Premier's annual fee is $99, compared to the $69 fee on the Plus, but the extra anniversary points should generally cover that increase.

Click here to learn more about the Southwest Premier card from Insider Picks' partner: The Points Guy.

Southwest Rapid Rewards Priority Credit Card

Generally, though, the Priority is the best option if you're a Southwest flyer.

That's because even though it has the highest fee - $149 - it offers at least that much in value each year, effectively cancelling out the fee.

The Priority offers 7,500 bonus anniversary points each year, as well as an annual $75 Southwest travel credit, which can be applied to purchases like flights. Assuming that Southwest points are worth 1¢ each - although you can usually get more value than that - that means that you're getting $150 of value each year just from these two benefits, which cancels out the annual fee.

The card also has a few other benefits, including up to four Upgraded Boarding certificates each year, meaning you can board earlier and choose your seat. You'll also get 20% back on in-flight purchases, and the same ability to earn tier qualifying points as the Premier card.

Ultimately, as long as you're willing to front the money for the annual fee, the Priority card pays for itself.

However, if you're absolutely set against the higher fee, the Plus and the Priority can be good options as well.

Click here to learn more about the Southwest Priority card from Insider Picks' partner: The Points Guy.

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