Scott Morrison's departments employ more than 95 communications staff and spin doctors, costing taxpayers at least $8 million a year.

Details released to the Senate show the departments of Immigration, Border Protection and Australian Customs have 85 permanent and 10 other staff responsible for media monitoring, internal communication and public relations.

This is estimated to cost between $8 million and $9.2 million a year in salaries alone, not including superannuation, leave, allowances and other costs. The details were released in response to questions asked by Labor senator Joe Ludwig.

Mr Morrison, who regularly uses the adjectives ''on water'' and ''operational'' to describe matters he will not discuss, said through a spokeswoman that ''any suggestion these staff are all working on the minister's liaison with the media is completely untrue''.

''These are large organisations, which require a significant amount of internal and corporate communication work on behalf of these agencies,'' the spokeswoman said.