<prompt> Human: How much will my credit score drop approximately for being 3 days late on my mortgage payment?  <response>: No one here could possibly answer this question, though people dont usually report late payments if theyre within 30 days of the due date.Now, most mortgages have a grace period of 15 days. When you say late, do you mean paying on Jan. 4 or Jan. 18? If paying Jan. 4, its not even a late payment. 