How do I improve my credit score quickly?

The fastest improvements: pay down revolving credit card balances to lower utilization; dispute any errors on your credit reports (get free copies at AnnualCreditReport.com); make sure no payments are currently late; and avoid applying for new credit. Becoming an authorized user on a card with a long history and low utilization can also give your score a quick boost. Most changes take 30–60 days to reflect.