20 Markkaa 1917

This note belongs to a series originally designed before Finnish independence but pressed into continued use well past 1917 — the date in the note's name reflects the year of the specific signature combination rather than a new issue. Finland declared independence in December 1917, but Suomen Pankki was already operating as a de facto central bank under Russian imperial authority, and the transition required no immediate redesign. The same plates served both empires.

The suffix designation D21 within the Pick numbering reflects one of several signature variants cataloged across this long-running type, making date and signatory identification essential to accurate attribution.