Elections to Comhairle nan Eilean Siar (Western Isles Council) were held on 4 May 2017, the same day as the other Scottish local government elections. The election was the third one using the nine wards created under the Local Governance (Scotland) Act 2004. Each ward elected three or four Councillors using the single transferable vote system: a form of proportional representation. A total of 31 Councillors were elected.