3,675. A Woman From a Kohein or Levi Family

Hilchos Bikkurim 11:10

A Yisroel born to a woman from a Kohein or Levi family need not be redeemed. This is because the obligation is based on the mother rather than the father as per Exodus 13:2 and Numbers 3:12, which tell us that the obligation applies to the first issue of the womb in Israel.

Hilchos Bikkurim 11:11

If a woman from a Levite family becomes pregnant from a non-Jewish man, the son need not be redeemed, but if a woman from a Kohein family becomes pregnant from a non-Jewish man, the son must be redeemed. This is because the mother has been disqualified from the benefits of a kohanic family.