The 2023 election to Newry, Mourne and Down District Council was held on 18 May 2023, alongside other local elections in Northern Ireland, two weeks after local elections in England.

[1] The Northern Ireland elections were delayed by 2 weeks to avoid overlapping with the coronation of King Charles III.

[2] 41 members were returned to the council via Single Transferable Vote.

The 2023 LG election in NMD saw the further decline of the SDLP and UUP, whereas Sinn Fein and Alliance made gains, with the DUP also gaining two councillors.

2019: 2 x Sinn Féin, 2 x SDLP, 2 x Independent 2023: 3 x Sinn Féin, 2 x Independent, 1 x SDLP 2019–2023 Change: Sinn Féin gain from SDLP 2019: 3 x SDLP, 1 x Sinn Féin, 1 x Independent 2023: 2 x Sinn Féin, 2 x SDLP, 1 x Alliance 2019–2023 Change: Sinn Féin and Alliance gain from SDLP and Independent 2019: 3 x Sinn Féin, 2 x SDLP, 1 x Independent 2023: 4 x Sinn Féin, 2 x SDLP 2019–2023 Change: Sinn Féin gain from Independent 2019: 2 x DUP, 1 x UUP, 1 x Alliance, 1 x SDLP 2023: 2 x DUP, 2 x Alliance, 1 x SDLP 2019–2023 Change: Alliance gain from UUP 2019: 2 x Sinn Féin, 1 x SDLP, 1 x UUP, 1 x Alliance 2023: 3 x Sinn Féin, 1 x DUP, 1 x Alliance 2019–2023 Change: Sinn Féin and DUP gain from SDLP and UUP 2019: 5 x Sinn Féin, 1 x SDLP, 1 x UUP 2023: 5 x Sinn Féin, 1 x SDLP, 1 x UUP 2019–2023 Change: No change 2019: 3 x Sinn Féin, 1 x SDLP, 1 x DUP, 1 x UUP, 1 x Independent 2023: 3 x Sinn Féin, 2 x DUP, 1 x SDLP, 1 x Alliance 2019–2023 Change: DUP and Alliance gain from UUP and Independent