The company was sued by district attorneys in Los Angeles, Riverside, San Diego and Santa Clara counties for allegedly making excessive phone calls to collect on past due accounts.
Prosecutors determined there had been alleged violations of California's Rosenthal Act and the Federal Debt Collections Practices Act going back to March 2015.
Capital One did not admit or deny anything under the stipulated judgment, which was reached during proceedings in Los Angeles County Superior Court, where the civil action was filed.
The company said changes would be made to prevent excessive debt collection calls over the next four years.
City News Service contributed to this report.