Public servants at the Australian Taxation Office have again emphatically rejected a new workplace deal under the government's hardline bargaining policy.

Commissioner Chris Jordan told his staff on Thursday afternoon that he was "very disappointed" at the 71 per cent no vote.

"There has been a 'no' vote by the majority of employees who cast their vote. Overall, 85% of eligible employees voted, and of these, 71.5% voted against the offer," the Commissioner wrote

"I am very disappointed that we didn't reach agreement.

"Given that the Government is likely to announce an election soon, we are not in a position to give certainty about the next steps at this time."

The result at the Tax Office comes on the back of Wednesday's no-vote at the Defence Department where 18,000 public servants rejected the proposed deal by a margin of nearly 55 per cent to 45, an increase on last month's knife edge no-vote.

The two results, so close to the likely announcement of an election and caretaker period mean the Coalition has failed to impose its industrial relations agenda on most of the Australian Public Service, with only about 30,000 workers, or 20 per cent of the workforce, signing up for agreements offered under the policy.

​More to come