Here’s how to combine multiple Citi credit cards for the ultimate travel rewards

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Frequent flyer points and miles can make it possible to travel for nearly free, and most travel rewards nowadays are earned with credit cards. But while having a single credit card in your wallet can help you get the trip of your dreams, if you truly want to maximize your rewards, you’ll want multiple cards in your wallet.

Now, that might initially sound like overkill, but with a little bit of understanding, you’ll find that pairing certain credit cards with one another is relatively easy. And fortunately, Citibank offers many credit cards that are designed to work together seamlessly. In fact, there are four specific Citi cards — we like to call them the “Citi Quartet” — that can be combined in ways that aren’t obvious at first glance, but which can turn your wallet into a powerful points-earning machine.

Let’s dive in to learn more about these four Citi credit cards and how you can make them work together to quickly earn a low-cost vacation.

Before we explain the Citi Quartet, we need to understand how Citi’s points program works. Citi’s travel rewards program is called ThankYou Rewards, and ThankYou points can be redeemed in many different ways, including for travel, gift cards, cash back and even statement credits. However, some of the best redemption options are only available if you have specific Citi credit cards.

One of those cards is the Citi Premier® Card. The Citi Premier offers the most flexibility when it comes to redeeming ThankYou points, because it allows you to transfer your points to Citi’s 16 airline partners, which includes American Airlines through Nov. 13.

These transfer partners require some work to understand, but they open up a lot of high-value redemptions, including the ability to redeem points for first and business class flights with just a reasonable number of points.

Only the Citi Premier has the ability to transfer points to partners … but here’s the good news. Any ThankYou points earned on any of your Citi credit cards can be combined into a single ThankYou account, and then get access to the best options and perks available to you across all your Citi cards. So if you have the Citi Rewards+® Card or the Citi Custom Cash℠ Card, the ThankYou points you earn with those cards can be transferred to Citi’s airline partners if you also have the Citi Premier card.

But not all Citi credit cards earn ThankYou points. Some of them, such as the Citi® Double Cash Card, earn cash back. However — and this is a trick that many people don’t know — if you also have a Citi Premier card, you can turn the cash back you earn with the Citi Double Cash into ThankYou points at a rate of 1 cent per point, and those points can then be used just like any other ThankYou points.

Related: From travel rewards to balance transfers, here are our favorite Citi credit cards.

So, with all that in mind, let’s look at the Citi Quartet. We obviously want the Citi Premier as part of our quartet, since it opens up the ability to transfer points to airline partners. Then, we also want to add the Citi Double Cash Card, the Citi Custom Cash Card and the Citi Rewards+ Card to complete the group.

Why all four? Well, let’s see what each of these cards brings to the table.

The Citi Premier is a must-have when you’re combining multiple Citi credit cards, as it’s the only card currently available that allows you to transfer your points to Citi’s partner airlines. Without this option, you’re limited to redeeming ThankYou points at a maximum of 1 cent apiece for options such as gift cards and booking travel through the Citi travel portal.

But with the airline transfer option, your points are potentially worth a lot more. Frequent flyer website The Points Guy values Citi ThankYou points at 1.7 cents apiece, thanks to the ability to transfer them to Citi’s 16 airline partners. Many of these partners are also part of larger airline alliances, opening up even more options.

If you don’t already have a Citi Premier, it’s a great place to start, especially right now since the card is currently offering new card holders 80,000 bonus points after you spend $4,000 in purchases within the first three months after opening the account. Based on The Points Guy’s valuations, those 80,000 points are worth as much as $1,360 toward travel.

Related: Here’s why the Citi Premier should be your first Citi credit card.

The Citi Premier also earns bonus points on many popular everyday household charges. You’ll earn 3 points for every dollar you spend on airfare, hotels, gas stations, supermarkets and dining (including takeout), plus 1 point per dollar on all other purchases.

You’ll also get an annual $100 credit on hotel reservations of $500 or more when you book through ThankYou.com with the Citi Premier, extended warranty protection, damage and theft protection, no foreign transaction fees, three free months of DoorDash’s DashPass food delivery membership and a $5 discount on three Lyft rides taken in a month.

The Citi Custom Cash Card is an extremely unique no-annual-fee credit card, as it’s most valuable wherever you spend the most money. It earns 5% cash back in your top eligible category each month on up to $500 spent per billing cycle, then 1%. The best part is there’s no need to select your bonus category in advance — Citi will automatically calculate which category you spend the most in each billing cycle and give you the extra rewards in that category.

You’ll also find that the Citi Custom Cash Card has a lot of eligible 5% cash back categories, including:

While the Citi Custom Cash Card is marketed as a cash back card, its cash back comes in the form of Citi ThankYou points that can be combined with the Citi Premier card. So if you have a Citi Premier, your 5% cash back category on the Citi Custom Cash effectively turns into a 5x ThankYou points category. But you can only transfer those points to Citi’s partner airlines when you have a Citi Premier card as well.

So which category should you aim to use your Citi Custom Cash Card for? Well, if you already have the Citi Premier in your arsenal, you can use that card to earn 3 points per dollar on airfare, hotels, supermarkets, gas stations and restaurants. So you’ll want to rely on the Citi Custom Cash for either transit, drugstores, home improvement, fitness clubs or live entertainment.

Related: This new credit card automatically earns 5% cash back wherever you use it most.

If those remaining categories aren’t typically places where you spend a lot of money each month, you might consider buying third-party merchant gift cards at a home improvement store such as Home Depot. For example, Amazon is a very popular gift card that you can purchase at Home Depot. You can then load that Amazon gift card into your own Amazon account and use it the next time you buy at Amazon.

The Citi Custom Cash Card currently features a sign-up bonus of $200 in cash back after you spend $750 on purchases in the first three months after opening the account. Again, that $200 is awarded in the form of 20,000 ThankYou points, so it’s an easy-to-earn bonus that can be a fast way to increase your ThankYou point balance.

If you’re looking to earn as many points as possible, you’ll want to include the Citi Rewards+ card in the mix. That’s because the Citi Rewards+ rounds up every purchase to the nearest 10 points, making it an ideal choice for small purchases.

For example, if you buy a pack of gum for $2, instead of earning just 2 points on that transaction, you’ll earn 10 points with the Citi Rewards+ card. That might not sound like a huge difference, but over time, it adds up.

You’ll also earn 2 points for every dollar spent at supermarkets and gas stations on the Citi Rewards+ card, up to the first $6,000 in purchases each year (then 1 point thereafter), and those purchases are also rounded up to the nearest 10 points.

Related: Round up your rewards with the Citi Rewards+ credit card.

Similar to the Citi Custom Cash Card, points earned with the Citi Rewards+ on its own can’t be transferred to Citi’s partner airlines, so you’ll need to pair the card with the Citi Premier to enhance your redemption options.

But the Citi Rewards+ brings a real advantage to the entire Citi Quartet party. That’s because when you redeem points with the Citi Rewards+ card, you’ll get 10% of your points back as a rebate, up to the first 100,000 points redeemed each year. And when you combine the Citi Rewards+ with other Citi ThankYou credit cards, this rebate includes all points redeemed from your combined ThankYou account.

The Citi Rewards+ card also offers an introductory 0% APR on new purchases for 15 months starting from when you first open the account, as well as an introductory 0% APR for 15 months on balance transfers made within the first four months after you open the account. Just be sure to pay off your debt before the intro periods end, because the APR rises to a variable 13.49% to 23.49% thereafter for both.

There’s one caveat to those looking to apply for the Citi Rewards+ card at the same time as the Citi Premier. Citi only allows you to earn a sign-up bonus in the same “family” of cards once every 24 months from the time you’ve opened or closed a card within that family.

This means if you recently applied for the Citi Premier, you’re still able to apply for the Citi Rewards+ card, but you won’t receive the sign-up bonus on both cards. Needless to say, you should prioritize getting the bonus on the Citi Premier first, since it’s a much higher 80,000 points versus the 20,000 bonus points available on the Citi Rewards+.

Simply stated, the Citi Double Cash Card is the best no-annual-fee card for purchases that don’t fall into any of the bonus categories on the other Citi credit cards, and the perfect choice to round out the Citi Quartet.

With the Citi Double Cash Card, you’ll earn 2% cash back on every purchase — 1% when you buy, and another 1% when you pay your statement. Although the Citi Double Cash doesn’t earn ThankYou points, you can convert cash back from the card to ThankYou points at a 1-to-1 ratio if you have the Citi Premier.

​​Related: The best cash back credit card: Citi Double Cash with no annual fee.

Aside from the card’s flat-rate cash back, the Citi Double Cash Card offers an introductory 0% APR for 18 months on balance transfers made within the first four months after opening the card (which rises to a variable 13.99% to 23.99% afterward). So it can also be a useful choice if you have existing credit card debt that you’re looking to consolidate at a lower interest rate.

While the Citi Double Cash is one of our favorite cards — and the benchmark credit card for CNN Underscored — it does have two downsides. First, it has a 3% foreign transaction fee, so this isn’t a card that you’ll want to carry with you when traveling abroad. Second, you must use your card at least once every 12 months to prevent your existing cash back from expiring.

So let’s put it all together. If you eventually have all four of these Citi credit cards in your wallet, you’ll end up with the ability to transfer points from all four cards to Citi’s partner airlines, a 10% rebate on all the points you redeem (up to 100,000 redeemed points per year), no foreign transaction fees, three free months of DashPass membership, discounted Lyft rides and an introductory 0% APR on new purchases and balance transfers.

You’ll also earn bonus points on many common purchases, such as 3 points per dollar on groceries, airfare, hotels, gas stations and restaurants using the Citi Premier, 5 points per dollar on the eligible category you spend the most in each month with the Citi Custom Cash Card, the ability to round up to the nearest 10 points on small purchases with the Citi Rewards+ Card and 2 points per dollar on all your other purchases using the Citi Double Cash Card.

Yes, you need to be OK with juggling multiple credit cards and knowing which card to use where, but if you can pull it off, it’s a great credit card strategy, especially if you’re looking to redeem your points for travel.

The one thing you need to keep in mind are Citi’s credit card application rules. Citi only allows you to apply for one Citi card every eight days, and a maximum of two Citi cards every 65 days. So if you’re looking to apply for all four of these cards, you’ll want to apply for two in the first two weeks — starting with the Citi Premier — and then the third and fourth at least two months later.

Alternatively, if you already have another Citi credit card sitting around that you hardly ever use, you can call Citi and ask if it can be converted to one of these four cards instead. But since you don’t earn a bonus when you convert an existing card, our recommendation would be to change it to either the Citi Double Cash Card or the Citi Rewards+ Card so you don’t lose out on any big sign-up bonuses.

Of course, if you don’t love constantly switching credit cards, you don’t have to have the entire Citi Quartet in your wallet. Even having some combination of two or three of these Citi credit cards will still be better than just having one of them. But if you’re looking to take your credit card rewards to the next level, the Citi Quartet is a great strategy to pull it off.

Learn more and apply now for the Citi Premier Card.
Learn more and apply now for the Citi Custom Cash Card.
Learn more and apply now for the Citi Rewards+ Card.
Learn more and apply now for the Citi Double Cash Card.

Looking for the best overall credit card? Find out which cards CNN Underscored chose as its best credit cards of 2021.

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