He left a will on 30 Aug 1711 in Charlestown. His estate was probated on 13 Sep 1711 in Charlestown, MA. The gravestone inscription in Charlestown, MA, reads:

Here lyes ye
body of
Mr. Isaac Johnson
who departed this life
Aug’t 31st 1711
in ye
62ed year
of his age.

”Isaac was born about 1649; married Mary Stone, the daughter of Nicholas and Hannah Stone, Nov. 22, 1671; and died about 1732, as her will was proved May 1, 1732. Isaac served in King Philip’s War, 1676, for which he was paid 5 s. ds. for services rendered. He is called a mariner in the records, but was apparently also a gunsmith. He lived in Charlestown, and became fairly well-to-do. He divided his property by will, of which his wife was the executrix.”