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How can I improve my credit score if I am not paying bills or rent?
When you say "promptly paying off the outstanding balance", do you mean you pay it off literally as soon as you have incurred the debt? It is important to actually let the debt post on a statement before you pay it off. If you pay it off before the statement posts then this won't help your credit at all. Once the statement posts you can pay the entire balance off before the due date and you will still pay no interest. Assuming you are allowing the balance to actually post on your statements, you can simply continue to do this and your credit score will improve over time as your account(s) get older and you show that you are reliable. The only other way to improve your credit score is to open more accounts. In the short term this will actually hurt your score, as it will decrease your average age of account and add an inquiry. However in the mid-long term, this will improve your score as having more accounts of a variety of types is better for your score. Having an installment loan such as an auto loan or home loan is good for your score as it is different from a credit card - however you should definitely not engage in one of these unless it makes financial sense for other reasons. Don't add debt just to build your credit score. You could just open more credit cards. Like I said it will hurt your score in the short term but improve it in the mid-long term. Open cards with a variety of benefits so you can use them for different things to get better rewards.