I've reviewed 100+ credit cards, and this is the one I'd recommend for keeping things simple

Choosing a credit card can often be a little stressful, between annual fees, reward categories, welcome bonuses and transferable points, there's a lot to manage and retain. I've been a reporter at CNBC Select for two years now, following my time covering personal finance topics for Fortune 500 companies. I've worked with hundreds of credit cards, some offering amazing travel benefits, others with huge statement credits.

But a credit card's perks are only as useful as you make them, so for the average person — something that doesn't require tracking but still offers some kind of advantage is ideal. Simplicity is its own perk. If you only want one, easy credit card in your wallet, this is the one that I'd recommend.

Ever since the Citi Double Cash® Card (see rates and fees) first came to market in 2014, it has quickly become a staple of the flat 2% back category of cards, earning 1% when you buy, 1% when you pay. This means that no matter where or what you're spending on, you're still earning a minimum of 2% back on your purchase. You don't have to worry about whether you're using the right card to maximize your dining rewards, and you'll always be earning the same flat rate, making it easier to track your rewards. There's no limit to the amount of rewards you can earn, and you don't have to opt in each month or activate any categories.

While the Citi Double Cash® Card technically earns cash back as Citi ThankYou® Points, these points can be redeemed for statement credits at one cent per point. While this won't get you the absolute maximum value, it can be a quick and simple way to slash your credit card bill for the month. The card also comes with a $0 annual fee, which is nice to see, with so many cards carrying costs upwards of $500 a year. This also means that you'll be in the black the moment that you start earning rewards, instead of having to "make back" the cost of the annual fee.

The card does offer a welcome bonus of $200 cash back after spending $1,500 on purchases in the first six months of account opening. As mentioned, since the card earns Citi ThankYou® Points, you'll have the option to redeem them in a few different ways. If you're still interested in travel but don't want the hassle of transferring points, you can use the Citi Travel Portal. While you'll still be redeeming your points for one cent a piece, you can spend your earned rewards on booking flights, rental cars or a stay at one of more than 1.4 million hotels and resorts.

The card also comes with an intro offer on balance transfers, which could be a good option for paying down any existing credit card debt while earning consistent rewards.

The Citi Double Cash® Card is one of a few cards that offers a flat 2% back, or you could consider a card that offers bonus categories for increased rewards, as long as you spend in those regularly.

The Wells Fargo Active Cash® Card is another 2% cash back card and offers a slightly improved welcome offer, earning $200 cash rewards bonus after spending $500 in purchases in the first three months. The rewards you earn can be redeemed for statement credits and gift cards, among other options. While this $0 annual fee card doesn't offer many additional benefits, you will receive up to $600 of cell phone protection against damage or theft, subject to a $25 deductible.

One minor difference is that the Citi Double Cash® Card is a Mastercard while the Wells Fargo Active Cash Card is a Visa, which will likely only matter if you shop at Costco, which only accepts Visa cards. Both of these cards offer fairly similar benefits, and you're decision will likely come down to the type of rewards earned, or the type of APR offer.

The Chase Freedom Unlimited® (see rates and fees) is not a flat rate card, and instead offers higher rates of rewards depending on the spending category. The card offers 3% cash back on drugstore purchases and dining at restaurants, including takeout and eligible delivery service, then 1.5% on all other purchases. While the 1.5% back on purchases is slightly higher than average, it's still below the flat 2% earned by other cards. The Chase card also comes with more partner benefits, despite having no annual fee, offering complimentary DoorDash and Lyft benefits.

With the Freedom Unlimited, you have a higher earnings potential, but need to spend in certain categories to earn the elevated rate. The redemption options are comparable, offering statement credits, gift cards or spending via Chase's travel portal, which offers an elevated 5% cash back with the Freedom Unlimited card.

While a flat 2% cash-back card like the Citi Double Cash Card can be a good fit for many people trying to simplify their credit card situation, the style might not fit for everyone.

• You value travel rewards: If you're at all interested in earning travel rewards, you're probably better off looking into more specific cards. While these cards often require a little more work to make sure you're getting the most value, they could be a better fit for your lifestyle.
• You want a more hands-on approach to your finances: With a 2% cash back card, you often don't get a lot of control over how and where you earn rewards. A card that offers categories could help you earn more rewards while still being in charge of your spending.
• You're looking for additional benefits: Cards with a $0 annual fee will often have fairly straightforward perks. If you're looking for benefits like travel protection or lounge access, you'll probably want a more premium card.

If you're working on building up your credit, the Capital One Quicksilver Secured Credit Card is a great secured option that still earns rewards. The card requires a $200 refundable minimum deposit, but earns a flat 1.5% cash back on all your purchases, rivaling some unsecured cards. Plus, you'll automatically be considered for a credit line increase, starting six months after you open the account.

The Citi Double Cash Card is one of the top flat-rate cash-back cards, a great option for those trying to make their wallet a little more manageable. You'll earn 2% cash back wherever you spend, without having to worry about specific categories or eligibility. While the card doesn't come with a ton of extra perks, it has no annual fee or limit on the rewards you can earn, making it a great option for earning rewards no matter where you swipe.

At CNBC Select, our mission is to provide our readers with high-quality service journalism and comprehensive consumer advice so they can make informed decisions with their money. Every credit card article is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of credit card products. While CNBC Select earns a commission from affiliate partners on many offers and links, we create all our content without input from our commercial team or any outside third parties, and we pride ourselves on our journalistic standards and ethics.

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