An election to all 30 seats on Mayo County Council was held on 24 May 2019 as part of the 2019 Irish local elections. County Mayo was divided into 6 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).
Following the recommendations of the 2018 LEA boundary review committee, there were significant alterations to the LEAs used at the 2014 Mayo County Council election. Its terms of reference set a maximum LEA size of 7 seats, breached by two of the 2014 LEAs. Other changes reflected population shifts revealed by the 2016 census.