After completing an apprenticeship as a bookbinder in his native town of Liverpool, William Moffitt was convicted of a theft and sentenced to seven years transportation in 1823. On the expiration of his sentence, Moffitt set up as a bookbinder, stationer, engraver and printer in King Street, Sydney, relocating to Pitt Street a few years later. His business prospered, and in 1842 he was able to take his wife and two daughters on a trip to England.
On his return Moffitt was for a time a director of the Australian Joint Stock Bank, but according to L. F. Fitzhardinge in the Australian Dictionary of Biography, 'in general [Moffitt] avoided public life, devoting himself to his business and to unobtrusive acts of private benevolence'.
Moffitt was among the most successful of early Australian booksellers and died in 1874 a wealthy man.