The first specific mention of the Council is during the reign of Tar-Meneldur the fifth King, in II 882. At that date its role and constitution was already well established, implying that it was rather older. Though no earlier reference exists, the Council may well have dated back to the time of the first King, Elros Tar-Minyatur.
The Council continued to advise the King throughout Númenor's history. It was still in place during the reign of Ar-Pharazôn the last King, and apparently continued until the time of the Númenor's Downfall in II 3319.