How long does it take to get your BSN after you received your ASN?

Do you mean add on? I have never heard it called that. Getting a BSN is simply a higher degree, your title, RN, is the same. It depends on the school that you go to and how many credit hours you take at a time. I have seen some school advertise that their RN-BSN program can be completed in one year or three semesters, but that refers to at least one calendar year and taking 12-16+ credit hours a semester, being a full time student. I would say the average is about two years and there is likely some additional general education course required for your BSN that you didn't need to get your ociates like statistics, chemistry, an additional english or writing course, etc. But you might check out the schools in your area that offer this type of program.