On 30 Oct 1766 when Amos was 19, he married Betty Brewster (43322) , daughter of Ichabod Brewster (23545) (15 Jan 1709/10-29 Jul 1797) & Lydia Barstow (24328) (1 Apr 1717-6 Feb 1815), in Lebanon, CT. Born on 10 Aug 1746 in Lebanon, CT. Betty died on 3 Apr 1838; she was 91.

Children of Amos and Betty (Brewster) Thomas, born at Lebanon, include Amasa Thomas,
Briggs Thomas, Lucy Thomas, Lydia Thomas, and Ruth Thomas.