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HMRC internal manual

Partnership Manual

Partnerships - formation

A partnership may exist without a written agreement, on the basis that a later written agreement gives formal expression to an oral agreement already existing. The date of the formation of the partnership remains the date on which the terms of the oral agreement were implemented.

Where, however, a written agreement creates a partnership where none exists already, it is effective only from the date of execution and implementation of the written agreement. It has no retrospective effect. Partnership agreements were held not to have retrospective effect in Ayrshire Pullman Motor Services & Ritchie v CIR [1929] 14TC754, Waddington v O’Callaghan [1931] 16TC187, and Saywell and others (trading as Eaton Tractor Co) v Pope [1979] 53TC40.