debitum in presenti, solvendum in futuro

A present indebtedness to be paid at a future time. "Although the duties thus accrue to the government as a personal debt of the importer, upon the arrival of the goods at the proper port of entry, yet it is but a debitum in presenti, solvendum in future, according to the Revenue Collection Act." Meredith & Ellicott v United States (US) 13 Pet 486, 493, 10 L Ed 258, 262.