The Curator of Art Louise Downey said that the only alternative would be that the pictures remained unseen in stores.
Only oil paintings are allowed to be displayed outside the museum.
Ms Downey said wall space was also needed for exhibitions, making it difficult to show as much of the public art collection as possible.
She said: "Our store as it is at the moment is full and because we've been tending to use our art gallery space at the museum for temporary exhibitions we have a lot of very displayable art in store.
"Two of the best paintings in the collection -the two portraits of Lillie Langtry - are on display, but it is difficult to find spaces within the museum buildings to display as much as we would like."
More than 200 publicly owned pictures are on show in the States, at the Royal Court, in the Bailiff's Chambers and in government offices.
Government House also has some important local pictures on its walls.
Ms Downey said this was just one way of getting pictures out of the store rooms.
"Museums are here to share our heritage and help people access our heritage so it is share what we have.
"We have large amounts of work on display in various locations around the island and they are all there to help people access our cultural heritage."
Oil paintings not needed for display in heritage trust buildings can be rented out to commercial concerns.
This provides income for the Heritage Trust.
Ms Downey said there was no difference between allowing a picture to be shown in a government office or a bank.
She said: "It is a money earner for us because we will loan out paintings to private companies.
"The bank staff and clients are as valid an audience as anyone else and in terms of our collections we would much rather have it out on loan than in store."
A shortage of wall space at Jersey Museum means that some pictures are displayed in other States-owned buildings.