This page provides a link to an article I published in Forerunners, the Journal of the Philatelic Society of Greater Southern Africa about postal rates in Botswana from independence in 1966 to 2017. It is an update to the work of Peter Thy published in the Runner Post, the journal of the Bechuanalands and Botswana Society in issue 26 in March of 1992.
The page also includes a copy of the Tariff Flyer for 2020 that provides new rates after the period covered in the article.