Leave (good) old debt on your report
Some people erroneously believe that old debt on their credit report is bad, Ulzheimer said. Negative items are bad for your score, and most of them will disappear from your report after seven years. However, "arguing to get old accounts off your credit report just because they're paid is a bad idea," he said.
Good debt -- debt that you've handled well and paid as agreed -- is good for your credit. The longer your history of good debt is, the better it is for your score. This is also a good reason not to close old accounts where you've had a solid repayment record.