ACT Pathology has operated eight collection centres in Canberra but as of May 17 the centres at John James Medical Centre in Deakin and the Macquarie Medical Centre will close.

Health Minister Katy Gallagher said it did appear counterintuitive that the government was closing the centres because it was facing increased demand for the services of the pathology centres.

But she said for the long term, it was the right decision to make, not least because of increasing demand being put on hospital resources.

Ms Gallagher also said more work would naturally be moved on to private pathology providers but she did not expect patients to be out of pocket. Public pathology services at the Canberra Hospital were under stress because of the increasing workload created by the community collection.

''We are having to refocus the pathology business,'' she said.

''We were getting so much work that it was starting to demand resources from our other areas of pathology.

''We're the only pathology service that has to offer the low-volume, expensive tests all the way down to the community testing whereas other private pathology providers don't have to offer all those services.

''Services in the hospital were coming under pressure because of the amount of community work that was being generated.''

Ms Gallagher said the centres at Macquarie and Deakin had been earmarked for closure because they were ''in places where other pathology providers are''.

''The public health service has to work out what's going to be its priority, particularly when there is a private service offering exactly the same and is able to do it and is able to bulk bill,'' she said.

''But if people wanted to still go to ACT Pathology, Macquarie is close to Calvary [Hospital] and John James is close to Canberra [Hospital], which will remain [open].''

Staff at the two closed centres will be redeployed, with no job losses. Four staff were affected.

Ms Gallagher said she had been told by private provider Capital Pathology that ''for the simple, straightforward tests they routinely bulk-bill all those tests anyway''.

''So it shouldn't be any increase for anybody in the hip pocket,'' she said.

Ms Gallagher said modest savings from the closures would be relocated elsewhere to the health system but that was not the government's motivation.

''It's really about containing the growth,'' she said.

Opposition health spokesman Jeremy Hanson did not criticise the closure of the centres. ''On the surface it makes sense to consolidate this service, however it is also important to ensure they remain available to the community. The opposition will monitor this initiative,'' he said.

The other ACT Pathology collection centres which will remain open are at the Canberra Hospital, the Gungahlin Health Centre, Lyneham shopping centre, Calvary Hospital, Tuggeranong Community Health Centre, and the West Belconnen Health Co-operative at Charnwood.