Department of Foreign Affairs and Trade officials told senators on Wednesday the agency would shoulder more than half the savings burden for the Coalition's measure to bring allowances in line with "community expectations".

Payments to be chopped covered household maintenance, cable and satellite TV, and outfits, while a child reunion supplement for diplomats will also cease.

The government will cut an allowance for diplomats to receive financial advice before moving overseas on foreign postings, DFAT secretary Frances Adamson said at a Senate estimate hearing.

"I feel we have a responsibility to staff to encourage them to be financially responsible, and there are complexities, but henceforth those arrangements at least for private financial advice will need to be undertaken as a personal matter," she said.

The crackdown, which will channel more funds towards the budget bottom line, comes after the government reviewed overseas staff expenses following controversy when it spent more than $200,000 sending 22 officials to Paris for a conference on how to save money.

Cuts to DFAT staff allowances will raise $21 million of the savings, while the removal of entitlements at the Defence Department will provide $13.5 million and Immigration another $5.3 million.

Diplomats serving in less dangerous cities will also lose a hardship allowance graded by the liveability of their location, while the government will apply limits to a cost of posting allowance expected to provide a bulk of the savings.

The Foreign Affairs department will grandfather the former allowance system for staff posted before cuts were made, Ms Adamson said.

"DFAT has chosen to exercise that option because we felt it was fairer to enable staff who were posted overseas in the expectation of receiving a certain amount of take home pay each week and who had arranged their finances accordingly, were able to conclude their postings on that basis."