The family lived in a house at 193 West 14th Street,[2] in what was then the northern frontier of New York City.

[4] Theodore became an apprentice in his father's firm and later was made a partner working with his brother Henry Osborne Havemeyer.

[5] His portrait was painted by the Swiss-born American artist Adolfo Müller-Ury, one is now in the New York State Museum at Albany; Müller-Ury also painted in 1891 a huge portrait of his wife Emilie de Loosey Havemeyer (Preservation Society of Newport County, Rhode Island (at Rosecliff).

The family owned many estates including, a town house in New York City at 244 Madison Avenue (on the southwest corner of 38th Street), a "cottage" on Bellevue Avenue in Newport, Rhode Island, and 500 acres in Mahwah, New Jersey, called Mountain Side Farm.

[9] Together, they were the parents of nine children, five daughters and four sons, including: Havemeyer died intestate at his home, 244 Madison Avenue in New York City, on April 26, 1897.