The St. Michael made two voyages from Calcutta to Port Jackson in the latter half of 1820.
On the first voyage, thirteen convicts were landed in Sydney on 28th September 1820. Amongst them were five out of the thirteen piratical convicts who had taken the Young Lachlan schooner in March 1819. They were wrecked on an Island on the Coast of Java and were seized and imprisoned at Batavia, where several died. The names of the five pirates who were brought back on the St. Michael in September 1820 were
Samuel O'Hara and
The St. Michael departed Port Jackson soon afterwards bound again for Calcutta where eight prisoners of the Crown were embarked. She returned to Port Jackson via Hobart in November 1820.
The following six convicts were listed as arriving on the St. Michael in November 1820:
James Crabtree - Weaver from Lancashire. Convicted in Bombay
James Fitzpatrick - Labourer from Longford. Convicted in Bangalore
Thomas Hill - Weaver from Lanarkshire. Convicted in Madras
John Merchant - Fisherman from Colchester. Convicted in Madras. Later sent to Norfolk Island
Thomas Brabazon - Labourer from Limerick. Convicted at Persian Gulf. Later granted an Absolute Pardon
John Hudson - Soldier from Lancashire. Convicted at Bombay
Free Passengers arriving on the St. Michael in November 1820 included Lieutenant Jacobs of the Bengal Army and Mrs. Jacobs. 
 Sydney Gazette 28 October 1820
 Sydney Gazette 4 November 1820