The FDA has become the latest union to accept the government's final offer on cuts to the Civil Service Compensation Scheme.
After talks with unions over the summer, the Cabinet Office in September outlined cuts to all three forms of redundancy pay for officials, but offered some concessions on its initial proposals.
The final offer has received a mixed response from unions, however, with the Public and Commercial Services union (PCS) branding the government's decision to revisit the compensation scheme just six years after a previous deal as "detestable and wrong".
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As the government’s deadline for a deal passed, the FDA said members had voted 89%-11% in favour of accepting the offer.
General secretary Dave Penman said that while his union still believed the changes were "unnecessary and unjustified", the FDA's participation in talks had shifted the government's position "significantly".
In a message to members, seen by CSW, he said: "We are waiting for official confirmation of the position of other unions that have responded in the timeframe stipulated in the offer.
"I am proud of what we have been able to achieve through tough negotiations and that members have recognised this by voting to accept the final offer.
"In what have been very difficult circumstances, we have moved the government significantly from its initial position where most civil servants facing redundancy would have received a maximum of 12 months' pay, early payment of pension would have been restricted and the Protocol for avoiding compulsory redundancies would have been all but torn up.
"Instead we have a maximum of 18 months' pay, have introduced new flexibilities to pension top-up and the Protocol has not only been strengthened, it now also covers the SCS [Senior Civil Service] for the first time."
Penman added: "We will now be involved in further discussions with the Cabinet Office over implementation issues and will of course update you on further significant developments."
It was announced earlier on Tuesday that members of Prospect – representing civil service specialists including engineers and scientists had voted "overwhelmingly" in favour of a deal.
The union said 83.99% of its members who took part in the ballot had voted to accept the deal, with 16% opposed. A Prospect spokesperson declined to provide details on turnout.
Responding to the ballot, deputy general secretary Garry Graham told CSW the government should "take no solace from the result" and said members remained "deeply angry" about the changes to the scheme, which come just six years after a previous deal with the Cabinet Office.
But he defended the decision to continue talks with the Cabinet Office over the summer.
"Had we refused to be at the table negotiating hard, it would have been an abdication of responsibility and would have provided the minister with the green light and excuse to impose far more detrimental terms prior to the summer recess,” he added.
PCS – the largest of the civil service unions and representing rank-and-file officials – is meanwhile still to consult its members, with a ballot due to run from November 7 to November 28.
A spokesperson for the union said the Cabinet Office had failed to provide enough time for proper consultation and the union is pushing for an extension to the October 31 deadline.
They said: "Our view is that as by far the biggest union we have a right to have a ballot on something so important as this, and the Cabinet Office should respect our members and respect the fact this process takes some time, so should wait for the result of that – particularly given how we asked for none of this, the whole thing has been imposed on us, and we were effectively shut out of the talks."
A Cabinet Office spokesperson declined to comment on whether the timing of the PCS ballot would affect the government's timetable for introducing the changes. Ministers have said they want to present the changes to parliament in early November.