As a younger son excluded from his patrimony by
primogeniture, he was expected to make his own fortune and left Clopton for the
City of London at an early age, where he was apprenticed in 1457 to the
mercer John Roo, and was admitted to the
Worshipful Company of Mercers in 1464. He served as Warden of the Company three times, in 1479, 1484 and 1488. On 15 October 1485 he was chosen as Alderman for
Dowgate ward. In 1486 he was elected
Sheriff of London during
Sir Henry Colet's term as mayor, and was himself chosen
Lord Mayor of London in 1491. By 1495 he was living in Bread Street. Although some biographers have stated that he was knighted, this does not appear to have been the case as he described himself in his will merely as "citizen, mercer and alderman". His vast fortune enabled him to become possessed of his ancestral estates at Clopton, the inheritance of his elder brother, and it is certain that the neighbouring town of Stratford-upon-Avon was his favourite place of residence. In about 1483 he erected there (in Chapel Street) "a pretty house of brick and timber", which was later purchased in 1597 and renovated by the playwright
William Shakespeare, and under the name of
New Place served as his residence until his death in 1616. Clopton rebuilt the nave of the Chapel of the Stratford Guild of the Holy Trinity, situated opposite his new house in Chapel Street, and he adorned the building with a tower, steeple, glass windows and paintings for the ceiling. He also built the
Clopton Bridge, a remarkably fine stone bridge of fourteen arches over the
River Avon, having removed at his own expense an old wooden bridge on the site. He also founded the Clopton
chantry chapel in the
Church of the Holy Trinity, Stratford-upon-Avon, still notable features of modern Stratford. ==Death and burial==