According to Alumni Cantabrigienses he became vicar of Marsworth, a Trinity living, around 1748; he took his mother's surname Pettiward in 1749 when he succeeded to her estates.
[6] Unlike his elder brother John and younger brother Daniel, who were sent to Trinity College, Cambridge,[7][8] Roger Pettiward went into business, apprenticed in 1769, for 1000 guineas, to William Gill of the London wholesale stationery firm of Wright & Gill, run with Thomas Wright.
Pettiward married Jane Seymour Colman (died 1856), a daughter and co-heiress (with her sister Laura, Lady de Trafford, wife of Sir Thomas de Trafford, 1st Baronet), of Francis Colman of Hillersdon House, Devon, who remarried secondly to Admiral Sir William Hotham (1772–1848); when her married name became Lady Hotham.
In 1832 Roger Pettiward owned the freehold of an orchard and market garden situated in the parish of St Mary Abbott's, Kensington, which by his will dated 13 May 1833 he devised to trustees to settle as the will directed.
She was succeeded in 1856 as life tenant by her husband's great-nephew Robert John Bussell (died 1908).