The 2017–18 North West Counties Football League season (known as the Hallmark Security League for sponsorship reasons) was the 36th in the history of the North West Counties Football League, a football competition in England. It was also the last season to have a single Division One. Teams were divided into two divisions: Premier Division and Division One. The constitution for Step 5 and Step 6 divisions for 2017–18 was announced by the FA on 26 May 2017, and ratified by the league at its AGM on 17 June.