Australian Statistician David Kalisch is set to leave the bureau when his five year term ends in December, after a near 38-year career in the Australian Public Service.

Mr Kalisch said he will leave the ABS as a more "collaborative, capable and productive organisation" than when he took on the top job in 2014.

"What I'm very proud of is the people who work here at the ABS, their professionalism, innovation and commitment and the value they deliver to the community each and every day," Mr Kalisch said

"The ABS is at the forefront, enabling safe and effective use of data to answer our nation's key questions and contributing to informed governments, business and households.

"The ABS is actively delivering the priority information we need, enabling informed policy choices, service delivery, a functioning economy, society and democracy."

But Mr Kalisch will also be remembered for the "censusfail" debacle, where the national survey website was shut down for two days in 2016 after being hit with four distributed denial of service (DDoS) attacks.

The Australian Signals Directorate was brought in to investigate the attack, while a subsequent review found the bureau and contractor IBM had not adequately planned for the crisis.

All eyes were also on Mr Kalisch for 12 minutes in 2017 when he delivered the results of the same-sex marriage survey.

At its peak, 500 bureau staff were working around the clock to roll out the postal vote, many moved off existing projects such as the 2021 census.

More than 12 million survey forms were posted, and while the forms were counted electronically, all envelopes had to be opened by hand.

Semi-trailers full of completed surveys were arriving on an almost daily basis.

"Everything was happening at breakneck speed and people had to respond to a tight timeframe," Mr Kalisch said last year.

And despite promising not to do a Rob Oakeshott, Mr Kalisch took his time to announce the results.

"It's probably the only time millions of Australians will gather to hear from an Australian statistician," Mr Kalisch joked at the press conference.

The agency has also undergone round after round of job cuts in the past few years, as it dealt with the efficiency dividend.

Treasury has already begun the process of recruiting a new Australian Statistician to lead the 2500-strong organisation.

The recruitment process will be chaired by the incoming secretary to the Treasury.