The Citi Simplicity Card is an excellent option for anyone who wants to pay less credit card interest because it offers a best-in-class 0% introductory APR. Before you can take advantage of what this card offers, you'll need to get approved. Your credit score goes a long way in determining your approval odds. Below, we'll detail the credit score requirement to get approved for the Citi Simplicity Card. Once approved, you'll receive a 0% intro APR on purchases and balance transfers. You'll get 12 months of intro APR on purchases from the date the account is open and a whopping 21 months of intro APR on balance transfers that you complete within four months of account opening.

Once the intro APR expires, a variable 19.24% to 29.99% APR applies. There is an intro balance transfer fee of 3% of the amount you transfer ($5 minimum) within the first four months from account opening. The standard transfer fee is 5% of the amount you transfer ($5 minimum). While this card doesn't earn rewards or offer a cashback program, the savings potential from the 0% intro APR can be extremely valuable. Let's say you have a 20% APR on an $8,000 credit card balance, if you planned on paying it off over 21 months, you would pay roughly $2,800 in interest. By taking advantage of the Simplicity Card's balance transfer offer, you'd pay a $240 transfer fee and could still save over $1,300.

Citi doesn't publish official credit score requirements, but you'll typically need a good to excellent score to have the best approval odds. There are various credit scoring models, but one of the most popular is the FICO score. This credit score falls into the following categories: poor (300-579), fair (580-669), good (670-739), very good (740-799), and exceptional (800-850). Your credit score is determined using several factors, and there are three major credit reporting bureaus (Experian, Equifax, and TransUnion). While each credit score is calculated differently, your score is generally based on your payment history (35%), amounts owed (30%), length of credit history (15%), new credit (10%), and credit mix (10%).

If your application is denied, you could apply for a different credit card with an intro-APR offer. However, these cards tend to have similar credit score requirements, so the best course of action is to focus on improving your credit score. The most sustainable way is to consistently pay your bills on time because your payment history is one of the biggest factors in your credit score. You'll also want to keep your debt and credit card balances as low as possible and ideally pay off your cards in full every month. Over time, these habits will help boost your credit score, but there are ways to work on your credit in the short term.

Tools such as Experian Boost and eCredable Lift could improve your credit score by allowing you to add additional information to your credit report, such as subscription services or payments to utility providers. Experian Boost is free and impacts only your Experian credit report; it only reports positive activity, so it won't ever negatively affect your credit score. On the other hand, eCredable Lift is a paid service that allows you to fill out your TransUnion credit report. It adds positive and negative history to your credit report, so you'll want to avoid using the service to add accounts that have late payments.

Another useful credit card that typically only requires fair credit or higher is the Citi Double Cash Card. It earns at least 2% cash back on all purchases (1% when you buy and 1% when you pay) and has a generous intro-APR offer on balance transfers. With a new account, you'll get a 0% intro APR for 18 months on balance transfers you complete within four months of opening the account (after that, a variable 19.24% to 29.24% APR applies). There is an intro balance transfer fee of 3% of each transfer ($5 minimum) you make in the first four months of account opening, and the standard transfer fee is 5% of each transfer ($5 minimum).

The Citi Double Cash Card is an excellent option for anyone who wants to transfer a credit card balance and save on interest. However, it normally requires a good to excellent credit score (670+), so only those with healthy credit profiles are likely to be approved. 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 story 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. We pride ourselves on our journalistic standards and ethics.