Trusts were established for the financial benefit of various members of the Day family. The first items in this record group are two ledgers containing accounts for Henry Lawrence Vincent Day; for the children of Robert and Blanche Day Ellis (Henry Day, Robert H., Fred E., and Elizabeth Ellis Jones); and Bernice Day Sharkey, daughter of Jerome Day. Other trusts were established for Barbara Flohr Day Whitesel, daughter of Henry Lawrence Vincent Day; Bernice Eugenia Day, daughter of Jerome and Lucy Mix Day, with Lucy Day, Henry L.V. Day and Stephen F. Heitfeld acting as trustees; and Lucy Mix Day; wife of Jerome, which was established for her benefit under her husband's will.

There are also records relating to the estates of several members of the Day family, including Eleanor Day Boyce, Helen Dwyer Day, and Lucy Mix Day. Several folders concern the probating of Jerome Day's estate.