Hammond settled in Trondheim, following a growing timber trade between Norway and England.

He eventually acquired land properties and forests, and was among the large merchants in Trondheim in the 17th century.

He ran a lumber trading business and held agriculture and forests in central and northern Norway.

Thomas Hammond perished during the 1681 Trondheim fire (18–19 April 1681) His wife died the following year.

Their son Wolliam Hammond Jr. (1707-1787) bought the estate Aagaard at Kalundborg, Denmark.