On 9 Oct 1760 when William was 26, he married Altjie Wheeler (27194) , daughter of Samuel Wheeler (10917) (ca 1713-1771) & Margareta Van Wert (ca 1700-14 May 1776). Born ca 28 Dec 1732 in Kinderhook, Columbia County, New York. Altjie died in Richmond, Ontario County, New York on 26 Apr 1805.

Children of William Fitch and Altjie Wheeler, the first five born at Kinderhook, Columbia Co., NY, the others at Pawlet:
    i. Abiel Fitch, b. 6 Mar 1762, d. 7 May 1829 at Richmond, Ontario Co., NY, m. at Pawlet 10 May 1781 Nathaniel Harmon;
    ii. Margaret Fitch, b. 7 Nov 1763, d. 24 Mar 1833 at Richmond, m. at Pawlet 25 May 1780 Philip Reed (b. 11 Jul 1756 at Norwich, CT, d. 20 Mar 1828 at Richmond);
    iii. John Fitch, b. 20 Feb 1765;
    iv. Jesina Fitch, b. 13 Feb 1767, m. Lemuel Chipman (b. 25 Jul 1754 at Salisbury, CT, d. 28 Apr 1831 in Ontario Co. NY);
    v. Rachel Fitch, b. 9 Sep 1768, d.17 Feb 1864 at Pawlet, m. there 14 Nov 1784 Ozias Clark (b. 14 Nov 1764 at Suffield, CT, d. 4 Jun 1855 at Pawlet);
    vi. Atlie Fitch, b. 24 May 1770;
    vii. Sybil Fitch, b. 24 Feb 1772, d. 14 Jun 1850 at Pawlet, m. Daniel Clark (b. ca. 1768 at Pawlet, d. there 1 Oct 1842); and
    viii. Anna Fitch, b. 28 Dec 1773, d. 17 Jan 1837 at Rochester, Oakland Co., MI, m. at Pawlet 3 Oct 1787 Cyrus Chipman (b. 3 Dec 1761 at Salisbury, CT, d. 17 Sep 1840 at Rochester).