Spirit of Tasmania is best known as the trading name of TT-Line (Australia).
It can also refer to the following ferries that have been operated by the business at some time during their careers:
Spirit of Tasmania – serviced the Devonport-Melbourne route, 1994-2002 – now known as Princess Seaways Spirit of Tasmania I – in service, Devonport-Melbourne then Devonport-Geelong, 2002–present Spirit of Tasmania II – in service, Devonport-Melbourne then Devonport-Geelong, 2002–present Spirit of Tasmania III – serviced the Devonport-Sydney route, 2003-2006 – now known as Mega Express Four Spirit of Tasmania IV Spirit of Tasmania V