Credit cards often have hidden fees and costs outlined in the fine print, and one of the most impactful of these is an interest rate hike after a missed payment. Many credit cards include a penalty APR, which is a higher interest rate triggered by a late or missed payment. This penalty APR can be significantly higher than the regular APR, sometimes reaching up to 29.99%. It's important to understand the conditions under which a penalty APR is applied, as it can lead to costly consequences for cardholders.

Other hidden fees to watch for in the fine print include foreign transaction fees, which are charges applied to purchases made outside of your home country. These fees can be as high as 3% of each transaction, adding up quickly for frequent travelers. Additionally, annual fees, late fees, and cash advance fees are other common hidden costs that cardholders should be aware of. Reading the cardit's terms and conditions thoroughly can help avoid these unexpected charges.