The best guaranteed approval unsecured credit cards for bad credit are the Fingerhut Credit Account and the Indigo® Mastercard® for Less than Perfect Credit, because both credit cards are designed for people with bad credit and both are easy to get approved for. To be clear, there are no credit cards with absolutely guaranteed approval. But some unsecured cards, like these two, are much easier to get than others. And both will help to build credit.
The problem with many unsecured credit cards for bad credit is they tend to be expensive. Many have annual fees and some have one-time fees or monthly fees, too. That’s on top of a high APR. Notably, the Fingerhut Credit Account has a $0 annual fee and no monthly fees. But it’s not a physical credit card, and you can only use the credit line at Fingerhut’s online store. So it’s not good if you need an emergency loan.
The Indigo Mastercard (for less-than-perfect credit), on the other hand, is a real credit card. In exchange for a $300 credit limit, you’ll pay an annual fee of $0 - $99, depending on your creditworthiness. And you can check to see if you pre-qualify before you apply, so at least you’ll know your approval chances before you get a hard pull on your credit.
Overall, the closest you can get to guaranteed approval for a credit card is with secured credit cards, which require an up-front security deposit. Secured cards aren’t going to provide an emergency loan, but they do help rebuild credit.