From 1969 onwards, the official legal announcements of changes to postal prices and services have been made in the form of "Post Office Schemes" printed in the official Government publication the London Gazette (and its companion editions the Edinburgh Gazette and the Belfast Gazette). They are thus a primary postal history source for the period.
The first few postal Schemes were amendments to the inland and overseas postal regulations laid down by statutory instrument, and came into operation from 1st October 1969 (at which point the Post Office became a public corporation). In 1971-72 the regulations were consolidated into new Schemes.
Most Schemes given here are amendments to the most recent complete Scheme, as altered by any previous amendments. This means it is sometimes necessary to track changes through several amendments in order to work out the actual rules and rates that applied at a given point in time. The amendments were periodically consolidated into new Schemes – themselves in turn subject to amendments, with further consolidated Schemes made at intervals.
The PDFs here are taken from the complete editions available on the Gazette web site. As these contain many other legal notices and can be over 100 pages long, the postal Schemes have been extracted for ease of reference. Most were taken from the London Gazette, but in some cases (where that was not available, or misprinted) the equivalent from the Edinburgh Gazette or Belfast Gazette has been used instead.
Note that while all changes were supposed to be announced via Scheme, this did not always happen in time, and there were sometimes mistakes or omissions in the Schemes when compared to (for example) leaflets issued to the public.