Methods that have a first leadhead that is the same as one of the leadheads found in the Plain Course of Plain Bob or Grandsire have been assigned a code according to the order in which the leadheads occur in its Plain Course. They are a useful shorthand for communicating the Lead order of a Method.

Originally lowercase letters were ascribed and these were later extended with numbers to cover higher stages. In the framework the codes associated with the letters p, q, r and s have been renumbered to include the leadheads previously omitted before the Differential classes were added.

Methods with Plain Bob leadheads are split into different leadhead groups according to the place notation (where n is the Stage) immediately before the leadhead as follows:

Methods with Grandsire leadheads are split into different leadhead groups according to the place notation (where n is the Stage) immediately after the leadhead as follows:

Any methods not falling in the above groupings are not given a leadhead code even if they have Plain Bob or Grandsire leadheads.