Senate powerbroker Nick Xenophon has declared he will refuse to provide his name on the 2016 census form this week amid privacy concerns and criticisms of recent changes made to the nationwide survey.

As well as volunteering himself as a legal test case, the South Australian senator - now with two party colleagues in the upper house and one in the House of Representatives - foreshadowed amendments to the relevant legislation.

This year, as well as being completed online, the census will retain people's names and addresses for four years rather than 18 months.

Senator Xenophon has joined a chorus of critical voices, including a former head of the Australian Bureau of Statistics, condemning the "unnecessary intrusion" and violation of the "inherent human right" to privacy.