What Credit Bureau Does Capital One Use?
A quick answer to this question is- Capital One often use reports from all the three credit bureaus; Experian, Equifax, and Transunion, whenever one is applying for one of its credit card.
It is still unclear as to why they conduct a triple-pull (from all the three credit report bureaus) or double-pull (from either of the two in case you have a credit freeze with one bureau) but this may be for purposes of avoiding mistaken credit report from one of the three credit bureaus.
It is true that the three credit bureaus issue reports of your credit score based on your financial activity, which means your credit report shouldn’t be different from each other.
However, mistakes do happen whereby you find out one of your reports was omitted by one credit bureau but is present in the other two. Therefore, they do a multiple pull to be sure of your credit report.
That’s why it is always advisable to regularly check your credit reports with three bureaus at least once a year to fix any mistakes that may have occurred. You can derive your annual credit reports from AnnualCreditReport.com