get into debt
To come to be in a position of owing money to someone or something (such as a bank or other lending institution). If you spend more with your credit cards than you can reasonably pay off, you'll get into debt before you know it.
run into debt
To come to be in a position of owing money to someone or something (such as a bank or other lending institution). If you spend more with your credit cards than you can reasonably pay off, you'll run into debt before you know it.