Often due to errors made by mail sorters, letters were forwarded to incorrect destinations. Special handstamps (SP 1 to 5) were used to identify this missent mail. Missent mail was also marked in manuscript. Two were in use in Cape Town G.P.O (SP 1 and SP 2). Port Elizabeth, Paarl, Robben Island, Grahamstown and Kimberley hd their own official handstamp for this purpose. The country postmasters were not provided with handstamps but made a manuscript note on the letter which they initialed, e.g. ‘Missent to Paarl’.
The Postmaster of Willomore used an improvised combination of marking the word ‘missent’in manuscript and a locally made stamp with the name ‘Willomore’ to mark ‘missent mail’.