The Commodore Clipper will be a freight-only service for the next four weeks.
Condor says it is to ensure supplies continue to get to the islands during the coronavirus outbreak.
From Monday, there will be no passengers or their vehicles sailing on the Clipper.
CEO Paul Luxon says it is to make sure ‘lifeline freight services are maintained’.
It is also creating a sterile environment for goods, meaning no personal contact with customers at its ports.
The ferry firm is looking at back up options for extra freight too.
Passengers due to travel on the conventional ferry over the period, which includes the beginning of the Easter holidays, can be moved on to the Liberation, or refunded.
Condor is also offering those who have decided against travelling the opportunity to amend their dates for free or accept a voucher to the value of their booking, valid for 12 months.

Tech-savvy course launches for Guernsey's older generation
New date confirmed for Guernsey charity sleep out
Move to plug leaks at one of Guernsey's most popular pools
Average rents in Guernsey keep climbing
Plans published for Guernsey's first island-wide by-election
Investigation launches following the death of an inmate at Guernsey prison
Dog tax in Guernsey may increase substantially
Guernsey gets behind community café after online appeal