On 14 Oct 1742 when Benjamin was 27, he first married Lydia Ballou (50770) , daughter of Samuel Ballou (49013) (12 Jan 1691/2-25 Jan 1765) & Susanna Arnold (33633) (ca 1704-bef 1761). Born on 6 Dec 1724 in Smithfield, RI. Lydia died on 26 May 1751; she was 26.

On 30 Jun 1752 when Benjamin was 36, he second married Mary Mann (37698) , daughter of John Mann (ca 1694-17 Feb 1782/3) & Abigail Arnold (18322) (ca 1688-ca 1775), in Smithfield, RI. Born on 6 Sep 1726 in Smithfield, RI. Mary died in East Hoosick, Berkshire County, Massachusetts, on 12 Jul 1787; she was 60.