As a widower he married a widow Susan Roussell at St Mary, Battersea in 1761; both were from that parish. Paul Callard (Grimwade p.457, 740) was a witness to the marriage.
The Will of Isaac Callard, silversmith late of Battersea, was proved for probate on 29th November 1770 (National Archives reference PROB 11/961/448).