Parliamentary Service spent nearly $400,000 on payouts for former staff in the second half of last year, a period in which the agency was mired in controversy.
Figures released by the Speaker showed that since June, 20 former employees had received a severance payment. On average, former staff received nearly $20,000 each.
Parliamentary Service employed around 650 people including assistants and advisers for MPs in Wellington and regional offices, and also staff within the parliamentary precinct such as security guards.
Eleven of the people who received severance packages had worked for MPs.
Parliamentary Service group manager shared services Anne Smith said the number and amount of payments was higher than usual because the agency was being restructured and because of a high turnover of MPs in the second half of the year.
She said the costs would be offset by the improvements made in the restructuring.
Labour Party MP Grant Robertson said that the payments reflected a turbulent period for the agency.
"It would be fair to say that morale has been pretty low in the Parliamentary Service and obviously from the point of view of MPs we don't want to see that carry on."
General manager Geoff Thorn resigned in August after it was revealed that Parliamentary Service had passed on emails between Fairfax reporter Andrea Vance and United Future leader Peter Dunne to an inquiry investigating the leak of a sensitive report.
Taxpayers' Union spokesman Jordan Williams criticised the costly use of public money to pay out former staff. He claimed that Parliamentary Service was "buying the silence" of workers who had been sacked on the spot by MPs.
A clause in parliamentary staff contracts allowed instant dismissal of staff in cases of "irreconcilable differences".
Mr Williams said he knew of two dismissals in which a minor party leader refused to hear their employee's response to allegations made by other colleagues.
Parliamentary Service would not confirm how many of the payments related to the irreconcilable differences clause, but said the agency followed strict processes in dealing with employment disputes.
The payments usually covered three months' wages and any outstanding leave or other entitlements.
The figures released did not include ministerial staff.
MP support staff: Eleven payments totalling $122,935.
Other staff: Nine payments totalling $273,006.