The answer can vary, depending on a variety of life events you can expect to happen over the next few months or years.
Home or car purchase on the horizon?
Wait until you lock in your loan. Your credit score plays the biggest role in your financial future when you're about to finance a major purchase. Locking in a low interest rate on your big-ticket items can save you thousands of dollars over the life of your loan. Responding to an instant approval credit card offer at a retail store or for a quick sign-up bonus could knock your credit score down enough that you land in a lower consumer tier -- and end up paying way more in finance charges on your larger loans.
Exception to the rule: If you're carrying too high of a balance on any one of your credit cards, you may want to use a balance transfer offer to reduce your overall credit utilization. Keep your formerly heavy account open to reflect a lower percentage of credit used across all your accounts.
Check your state's employer reporting rule first. Although lawmakers have proposed a ban on credit checks by prospective employers, the practice remains legal in most states. In fact, nearly half of American companies run a credit check as part of their applicant screening process. Too many credit card applications in a short period of time can cause your resume to land in the "high risk" pool. If your state hasn't already banned employer credit checks, wait until you're in your new job for at least 30 days before you apply for another credit card.
Just looking for good credit card deals?
Wait about 60 days or longer. If you're just trying to scope out the best rewards credit cards on the market, or if you want an upgrade to a card with more features, wait a few months between applications. Unlike mortgage and car loan applications, credit card applications don't get lumped together during a tight time period. Every new review of your credit can drop your credit score a few more points than the last, making it tougher for you to earn low APRs or high sign-up bonuses right after completing a credit card application.