The changes will see the position of High Sheriff join the Lord Mayor and Deputy Lord Mayor positions in being allocated proportionately and fairly for the first time.
The move follows months of engagement across all political parties and despite the DUP and UUP attempting twice to block the change, the PUP broke away in abstaining on the issue.
Councillor Michael Long said; “I am pleased that my proposal to ensure fairness and equality in terms of all the civic posts has been accepted. Until now the position of High Sheriff had simply been carved up by the two main Unionist parties, but this will no longer happen.
“From now on any parties who wish to nominate for the post will be able to do so using the D’hondt system.
“Over the past few months Alliance has tried to get an agreement with the various Unionists parties on this, but despite months of talks, there was no progress, which is why we have gone forward with the motion this month, ahead of the nomination process in November.
“We had hoped to introduce a system which might favour the inclusion of members from smaller parties but the failure to get Unionist support for the change has meant that we have had to go with the D’hondt proposal, at least in the interim.”