Since Tadaaki MATSUDAIRA who was his half brother and the second lord of Kameyama Domain was sickly, Tadachika became his adopted child and inherited the family estate and assumed the position as third lord of Kameyama Domain.
異母兄で亀山藩の第2代藩主・松平忠昭が病弱だったため、兄の養子となり、天和(日本)3年（1683年）に家督を継いで亀山藩の第3代藩主となる。