This series contains the register of the Privy Council, comprising the minutes of its proceedings, its orders, certain proclamations and the reports of committees with the papers accompanying them, sometimes entered at length, sometimes in abstract only. Pieces 1-873 are fully indexed. There are several gaps in the series of registers, the chief being that between 1 January 1602 and 1 May 1613.

From the late sixteenth century the registers generally contain lists of privy councillors and, occasionally, lists of committees and committee members, transcripts of official oaths, etc. From the mid 1890s, maps and plans frequently appear in the registers. They relate mainly to local authority areas and ward boundaries arising from the issue of orders in council in connection with the grant of charters, etc. Other maps relate to the boundaries of ecclesiastical parishes, chapelries, benefices and the extent of military manoeuvres.

Also included are a number of volumes containing copies of revised king's regulations and Admiralty instructions, issued under orders in council.