Q: If you were to hit  a high default interest rate on a 0% interest intro credit card; will it place a negative mark down on your credit report?

A: If I understand your question, you had a credit card with a teaser rate of 0%, but then were late on a payment and it went to a default rate.

Those default interest rates typically range from 25% to 30% or so.

Even though you were late on your payment, it will not necessarily be reported to the credit bureaus. It depends on how late the payment was received.

Banks and credit card issuers can legally report your delinquency if it is 30 days or more late.

But if you were just a day or two late, or even a week or two, that will not show up on your credit reports.