The first editor of the Calendar of State Papers, Colonial brought together all the papers from different sources (dated not later than 1688) that he wanted to print in the Calendar, which was intended to end in 1688. They were placed in date order and now form the series C.O. 1, Colonial Papers: General Series. These are available online through the Colonial State Papers database
The same procedure as was used in C.O. 1 was followed for later volumes. From 1688 until 1807 the records relating to the American colonies are combined in C.O. 5 , America and West Indies: Original Correspondence etc. In spite of its title, C.O. 5 does not include records of the colonies of Canada and the West Indies and includes only one, the Bahamas, which did not come to form part of the United States.
All of C.O.5 is being digitized as part of the above database.