The average credit card APR is well over 17%, but some balance transfer cards have 0% introductory offers. Here are the best picks for paying down debt without interest

Why you'll love it: The Citi Simplicity Card offers the longest introductory offer in the business — a full 21 months with 0% APR.

Consumers with a lot of high-interest credit card debt could save more with a card that offers 0% for as long as possible. The Citi Simplicity Card extends one of the best offers in this category.

There's no annual fee, yet you get 0% APR on balance transfers for 21 months (transfers must be completed in the first four months) and 0% APR on purchases for 12 months. After that, your rate goes up to 16.99% to 26.99% based on your creditworthiness. Other perks this card offers include automatic account alerts, 24/7 customer service, and the ability to choose your payment due date.

Having a full 21 months with 0% APR could help you pay down a ton of debt, but keep in mind you'll pay a 5% balance transfer fee (minimum of $5) for the privilege, and you need to make all transfers in the first four months.

Pros: Score 0% APR for a full 21 months, no annual fee

Cons: 5% balance transfer fee, few cardholder perks

Why you'll love it: This card offers 0% APR on purchases and balance transfers for a full 18 months, making it ideal for balance transfers or big purchases.

The U.S. Bank Visa Platinum Card is unique in the fact that it offers 0% APR on more than just balance transfers. Once you sign up, you'll get the introductory rate of 0% on balance transfers and purchases for 18 months (followed by a 14.74% to 25.74% variable APR).

Getting 0% APR on balance transfers and purchases makes this card a solid option for anyone who has debt to transfer or a big purchase to make. If you wanted to buy new appliances or use credit to cover a minor kitchen remodel, for example, you could do so and repay your balance at 0% APR for the full 18 months.

Other benefits you'll get with this card include cell phone protection, a free TransUnion credit score each month, and the ability to choose your payment due date. This card also comes with no annual fee, although there is a 3% balance transfer fee.

Pros: 0% APR good for both balance transfers and purchases, no annual fee, cell phone protection

Cons: 3% balance transfer fee

Click here to learn more about the U.S. Bank Visa Platinum Card.

Why you'll love it: You'll earn 5% back on up to $1,500 spent in categories that rotate each quarter plus 1% back on everything else. Get 0% APR on purchases and balance transfers for 14 months.

Consumers who want to make a big purchase and pay it off slowly over time should consider the Discover it Cash Back. Not only does it offer 5% cash back in categories that rotate each quarter and 1% back on all other purchases, but Discover will also double all the rewards you earn after the first year.

The Discover it Cash Back doesn't charge an annual fee, and you qualify for free Social Security number alerts, no foreign transaction fees, and no late fees on your first late payment.

Once you apply, you can qualify for 0% APR for 14 months on purchases and balance transfers. Just keep in mind that there's a 3% fee for balances transferred to the card. Then, there's a variable rate of 14.24% to 25.24%, and after October 10, 2019, the balance transfer fee will increase to up to 5%.

Also be aware that it's rarely a good idea to use credit cards to earn rewards when you're in debt. If you keep using your credit card while trying to pay down your balance, you may keep adding to your debts and prevent yourself from paying them off.

Pros: Earn cash back for your purchases, 0% APR for 14 months

Cons: Rewards can entice you to spend more, shorter 0% APR offer than some other cards

Click here to learn more about the Discover it Cash Back card.

Why you'll love it: This card offers a solid introductory APR on purchases and balance transfers, and it also earns you valuable American Express points.

If you're working to pay down a large credit card balance, earning points or miles shouldn't be your priority. The value of the rewards you earn will be dwarfed by any interest charges you incur.

But if you're able to pay off your balance during the 0% intro APR period, the Amex EveryDay card provides a nice opportunity to earn Amex points that can be transferred to travel partners like Delta and Marriott.

The EveryDay card has no annual fee, and it has an intro offer of 0% APR on purchases and balance transfers for the first 15 months. There's no fee for balance transfers, but just note that they must be completed in the first 60 days after account opening.

After 15 months, the APR is a variable rate of 15.24% to 26.24%.

The EveryDay card earns 2x points at U.S. supermarkets on up to $6,000 per year (then 1x) and 1 point per dollar on everything else. If you make at least 20 purchases in a billing period, you'll get a 20% points bonus, too.

Pros: Earns Amex points, no annual fee, solid intro APR offer with no fee for balance transfers

Cons: Rewards could entice you to spend more

Click here to learn more about the Amex EveryDay card.