Folding a Business Letter to fit a C6
Size envelope.
The C6 envelope is one of the most popular standard
envelope sizes. The dimensions of a C6 envelope are
114 mm x 162 mm.
A C6 envelope can hold a piece of A4 paper that has
been folded into quarters, or a piece of A5 paper that
has been folded in half.
The A4 page shown below is standard business
letter size. You would fold from bottom to top in ½
and then again in half to fit the envelope.