There is provided an encoding method for encoding a two-dimensional code using an encoder, wherein in accordance with a predetermined area allocation policy, the encoder generates a primary two-dimensional tally code having a primary effective area containing primary distribution information and a primary dummy area, and generates a secondary two-dimensional tally code having a secondary effective area containing secondary distribution information and disposed in a position where the primary dummy area is disposed and a secondary dummy area disposed in a position where the primary effective area is disposed.