2019 Dún Laoghaire–Rathdown County Council election

An election to all 40 seats on Dún Laoghaire–Rathdown County Council was held on 24 May 2019 as part of the 2019 Irish local elections. Dún Laoghaire–Rathdown was divided into six local electoral areas (LEAs) to elect councillors for a five-year term of office on the electoral system of proportional representation by means of the single transferable vote (PR-STV).

Boundary changes
Following a recommendation of the 2018 Boundary Committee, the boundaries of the LEAs were altered from those in used at the 2014 election. Its terms of reference required no change in the total number of councillors but set a lower maximum LEA size of seven councillors, requiring a change to the eight-seat Dún Laoghaire LEA. Other changes were necessitated by population shifts revealed by the 2016 census.

Overview
After the 2019 election, Dún Laoghaire–Rathdown became Ireland's first 50:50 gender-neutral Council. Fine Gael remained the largest party gaining an additional 2 seats while seeing a slight reduction in vote-share. Fianna Fáil lost a seat in Stillorgan to return 7 in total and saw a slight reduction in vote share. The main winners in Dún Laoghaire were the Greens who won 6 seats and saw all 6 of their candidates elected in the process. They topped the poll in 4 of the 6 LEAs. Labour gained a seat in Dun Laoghaire but lost seats in Stillorgan and Glencullen–Sandyford to reduce their numbers to 6 seats overall. Solidarity–People Before Profit lost a seat in Dún Laoghaire to only return with 2 seats while Sinn Féin had a terrible election losing all 3 of their seats.