The public service dinner that cost taxpayers $1889

The $1889 dinner was for 11 Airservices Australia officials who were farewelling a colleague.

Nationals senator Bridget McKenzie quizzed Airservices Australia CEO Jason Harfield on the dinner, which he attended, at Senate estimates on Wednesday.

"On average, 11 people earning over $400,000 a year having a free dinner ... thanks to the taxpayer," Senator McKenzie said.

Mr Harfield confirmed the dinner was held after a monthly manager's meeting in Canberra and included alcohol.

"This isn't something you do after every management meeting is it?" Senator McKenzie asked.

Mr Harfield said if all the managers were in town for a meeting, "normally we would have dinner at some stage".

Exactly which restaurant the public servants chose to dine at remains a mystery.

"I won't promote the restaurant," Senator McKenzie said.

Senator Bridget McKenzie cited a document produced via freedom-of-information laws which detailed the expense.

It showed two card charges: $687 for four local staff members and another for more than $1200 for the other seven attendees.

It was common practice for the most senior person in the room to charge the meal to their card, Mr Harfield said.

He confirmed the average salary of those in attendance was about $400,000, though Senator McKenzie said there were a couple of people earning more than $500,000.

In 2022-23, Mr Harfield earned a total $1,030,335, which included a base salary of $871,632 plus superannuation and other benefits.

It's not the first time a Canberra dinner has come into question at Senate estimates.

The education department was criticised earlier this year for a "flagrant waste" of taxpayer funds, after spending $1200 on a dinner at local fine-diner Courgette.