If you’re in the market for a loan, mortgage, job, or even an apartment to rent, you could be impacted by your FICO score. This is the score that most lenders and some employers and landlords use to determine whether you’re a credit-worthy individual. A low score means you’re considered high-risk, and you can be denied housing, jobs, or loans because of that risk. Some lenders will take on high-risk customers but will charge significantly higher interest rates that could cost you thousands of dollars over the life of a high-principal loan, such as a mortgage or car loan.

Knowing what factors influence your score gives you a lot of power to improve your rating. The largest part of your score is based on your payment history. Some people fall into the habit of skipping payments or paying late during lean times and then make hefty payments to compensate when cash does come in. For credit rating purposes and to avoid late fees, it’s much wiser to make minimum payments on time every month. Another factor that influences your score is the average age of your credit. You can manage this by not closing out old accounts (even if you’re not using them) and by not applying for a lot of new credit all at once.

FICO scores are complex, and rebuilding a poor one takes time. But if you don’t understand how the score works, your efforts to improve it could wind up having the opposite effect. Learn more about FICO scores by taking this quiz fromHealthIQ.com.