Everything you need to know about the Fidelity Rewards Visa Signature Card

A good cash-back credit card can help you earn anywhere from 1% to 6% cash back on your spending. But cash-back investment cards take this concept one step further, allowing cardholders transfer their points into an investment vehicle that earns compound interest on top of their rewards.

The no-annual-fee Fidelity® Rewards Visa Signature® Card is one such card. Fidelity account holders can earn 2% cash back on all eligible spending, which is the highest flat-rate cash-back rate among investment credit cards. Every $2,500 you spend charge to your Fidelity Rewards card equals a $50 deposit into your eligible Fidelity investment account(s).

Below, CNBC Select breaks down the rewards, benefits and fees associated with the Fidelity Rewards Visa Signature Card to help you decide if it's the right card for you.

• Rewards
• Additional benefits
• Fees
• Bottom line

Cardholders with a qualifying Fidelity investment account can earn unlimited 2% cash back on all eligible spending, with no categories or limits on reward points earned. They can then put that cash directly back into the market.

Every eligible $1 spent equals 2 Reward Points, which don't expire. Points can be deposited in up to five qualifying Fidelity accounts at once. Eligible accounts include most nonretirement accounts as well as the following:

• Traditional IRA
• Roth IRA
• Rollover IRA
• SEP IRA
• Fidelity Charitable^® Giving Account^®
• Fidelity HSA^®
• Fidelity^®-managed 529 College Savings Plan accounts

Terms apply for all eligible accounts, subject to IRS rules.

The 2% cash-back rewards value applies only to the points you redeem for a deposit into an eligible Fidelity account. You can choose to redeem your points for other rewards such as travel, merchandise, gift cards, and/or statement credit, but the redemption value could possibly be less.

Using data from the data location firm Esri, CNBC Select estimates that the average American spends about $1,844 in retail purchases per month (see our methodology). Using Fidelity's cash-back calculator, charging $1,800 per month to your Fidelity Rewards Visa Signature card could translate to $432 cash back in a year and $19,312 in your investment portfolio over 20 years. 

Like all Visa Signature^® cards, the Fidelity Rewards card comes with a number of perks, including 24-hour concierge service; special offers on travel, dining, sporting, entertainment and shopping; emergency cash and card replacement; travel and emergency assistance services; accident services and auto rental collision damage waiver; lost luggage reimbursement; and roadside dispatch.

You can make contactless payments with this card, so all you have to do is tap to pay at checkout (where that service is available).

The card also has zero-fraud liability, so if your card is used without your consent and you report it, you won't be held liable for the costs.

Terms apply for all benefits.

The Fidelity Visa Signature Card has no annual fee. There is no foreign transaction fee if you use this card abroad. If you plan on traveling abroad, you might want to consider opening a card with no foreign transaction fees, such as the Capital One VentureOne Rewards Credit Card. (See rates and fees)

The Fidelity® Rewards Visa Signature® Card has no caps or expiration on reward points, and you won't have to pay an annual fee. On top of being able to invest your cash back, cardholders can enjoy complimentary concierge assistance when booking travel and concert tickets, along with Visa Signature travel and shopping offers at hotels and premium retailers.

But the biggest appeal of this card is the chance to grow your cash back with compound interest over time. Your cash back can go even further when it's invested in the stock market and can offer long term returns.

If you invest with a brokerage firm other than Fidelity, you may want to check out their credit card offerings, including the American Express Platinum Card® for Schwab or the TD Ameritrade Client Rewards Card.

Our methodology

To determine which credit cards offer the best value, CNBC Select analyzed popular credit cards available in the U.S. We compared each card on a range of features, including rewards, welcome bonus, introductory and standard APR, balance transfer fee and foreign transaction fees, as well as factors such as required credit and customer reviews when available. We also considered additional perks, the application process and how easy it is for the consumer to redeem points.

CNBC Select teamed up with location intelligence firm Esri. The company's data development team provided the most up-to-date and comprehensive consumer spending data based on the 2019 Consumer Expenditure Surveys from the Bureau of Labor Statistics. You can read more about their methodology here.

Esri's data team created a sample annual budget of approximately $22,126 in retail spending. The budget includes six main categories: groceries ($5,174), gas ($2,218), dining out ($3,675), travel ($2,244), utilities ($4,862) and general purchases ($3,953). General purchases include items such as housekeeping supplies, clothing, personal care products, prescription drugs and vitamins, and other vehicle expenses.

Taking this annual budget of $22,126 and dividing it into monthly categories, CNBC Select estimates that the average American monthly spend is $1,843.83.

CNBC Select used this budget to estimate how much the average consumer would save over the course of a year, two years and five years, assuming they would attempt to maximize their rewards potential by earning all welcome bonuses offered and using the card for all applicable purchases. All rewards total estimations are net the annual fee.

While the five-year estimates we've included are derived from a budget similar to the average American's spending, you may earn a higher or lower return depending on your shopping habits.

Information about the American Express Platinum Card® for Schwab has been collected independently by CNBC and has not been reviewed or provided by the issuer prior to publication.