The number of TDs in the next Dáil could rise by as many as 21 from the current 160 in response to an increase in the population.
The Electoral Commission, a body established in May of this year, will report on Wednesday on how many additional TDs are required and on the makeup of the constituencies that elect them.
In order to take account of Ireland's growing population, the commission has been given a remit to create between 11 and 21 additional seats.
This would bring the number of TDs in the 34th Dáil to between 171 or 181. This will be the first time the number of TDs has grown since 1981.
Red-hot interest
It is almost impossible to understate the significance of this report. In the words of the commission, it will represent the "most important reform of the electoral system in decades".
In order to accommodate the extra TDs, every one of the country’s 39 constituencies is likely to change.
In a recent press conference, Minister for Public Expenditure Paschal Donohoe told journalists there is "red-hot interest all over the political system" about the contents of the report.
Minister Donohoe, whose constituency of Dublin-Central has had a series of boundary revisions since 2016, said: "I have a keen memory of what that moment is like when the maps come out and we all sit down to unfold the maps to see what the boundaries of our constituency are going to be."
Outside of the political bubble, there is interest too, more than 500 individuals and political parties made a submission during the public consultation phase.
Since May, the commission has been reviewing every constituency through the lens of Article 16 of the Constitution, which allows for one TD per 20,000 to 30,000 people.
Within those criteria, they must also ensure that the ratio remains broadly the same across the country.
Tim Carey of the Electoral Commission has previously characterised the process as "iterative", meaning that the number of TDs cannot be decided upon in isolation but must be considered in tandem with the boundary changes.
Constituency boundaries
The terms of reference for the commission say each constituency should be composed of "contiguous areas" and that "the breaching of county boundaries shall be avoided as far as is practicable".
However, the commission has admitted that it will not be possible to avoid this in all areas around the country.
Many of the submissions to the commission highlighted the importance of the county boundary to ensure people are not "disenfranchised" and "marginalised" when they end up being part of an "add-on" to a neighbouring constituency.
Fianna Fáil argued that preserving county boundaries is important for "civic engagement".
"The commission should take an approach which seeks to make the boundaries less likely to require major divisions in the future," the party said.
In its submission, Fine Gael noted that "eight constituencies include parts of (ten) neighbouring counties".
These include the likes of the Cavan-Monaghan constituency, which includes parts of Co Meath; Galway West, which contains parts of Co Mayo; and Sligo-Leitrim, which contains parts of Donegal and Roscommon.
Fine Gael TD Alan Farrell told RTÉ’s Morning Ireland this week that it can also create problems for TDs trying to get access to services for constituents, as it means they have to deal with multiple local authorities.
On the same programme, Sinn Féin TD Kathleen Funchion, who is elected in the five-seat Carlow-Kilkenny constituency, said a lot of people locally would welcome it being broken into two separate three-seaters.
Seat numbers
There are currently nine three-seat constituencies, 17 four-seaters and 13 five-seaters and this will be one area to watch when the report is published.
In recent years, the trend has been to move away from three-seaters, which have a much higher quota (25%) and so can favour the larger parties and incumbents.
In submissions, Sinn Féin, Labour and People Before Profit all called for a reduction in the number of three-seat constituencies.
The Labour Party pointed out that proportional representation (PR) is designed to ensure that there are as few "wasted" votes as possible.
Sinn Féin said three-seat constituencies "reduce the diversity of representation that our PR-STV electoral system is designed to deliver".
People Before Profit called for an amendment in the Electoral Act to allow six-seat constituencies in the future.
Where will benefit?
The areas with the highest growth in the Census are predominantly along the east coast; Longford (+14%), Meath (+13%), Fingal (+11%), Kildare (+11%), Wexford (9%) and Carlow (9%). These areas are likely to be the main beneficiaries of additional seats.
Dublin alone elects almost one-third of Dáil deputies; 45 TDs across 11 constituencies, and, according to the Census figures, there will have to be a commensurate increase.
However, the Census does show population increases across every county in Ireland between 2016 and 2022 and, given the likelihood of widespread boundary changes, the extra seats will not be exclusively on the east coast.
The commission is also tasked with examining the constituencies for the European Parliament election, which will take place in June 2024.
The parliament has indicated Ireland will be in line for one additional seat, however this has not yet been formally ratified.
As a result, the commission is likely to make a recommendation to retain the current status quo.
The CEO of the Electoral Commission, Art O’Leary, has described the boundary redraw as "a battle between maths and geography".
Once published, politicians might see it as the point at which "red-hot interest" becomes either relief or regret.
The constituency review will be laid before the Houses of the Oireachtas on Wednesday morning at 8am and it will be made public a short time later.
To achieve this, it will have to balance complex mathematical and geographical concerns to deliver 39 constituencies that are recognisable as "coherent and contiguous".
