Through Draper's influence Osborne obtained a small official employment under the Commonwealth. After the publication of his "Advice to a Son" in 1656, he gained a wide reputation, and paid many visits to London, he reckoned the philosopher Thomas Hobbes among his friends. He died at Draper's house at Nether Worton, near Deddington, Oxfordshire, on 11 February 1659, and was buried in the church there. His son John Osborne moved to Ireland, where he became Prime Serjeant, and died there in 1692.