The following elections occurred in the year 1921.
- 1921 Belgian general election
- 1921 Italian general election
- 1921 Northern Ireland general election
- 1921 Norwegian parliamentary election
Africa
Asia
Americas
- Canada
- 1921 Guatemalan presidential election
- United States
Europe
- 1921 Belgian general election
- Irish elections
- 1921 Northern Ireland general election
- Italian general election
- Norwegian parliamentary election
- 1921 Portuguese legislative election
- Free State of Prussia (Germany): Landtag of Prussia election
- 1921 Swedish general election
- United Kingdom:
- 1921 Bedford by-election
- 1921 Orkney and Shetland by-election
- 1921 Cardiganshire by-election
- 1921 East Dorset by-election
- 1921 Lewisham West by-election
- 1921 Louth by-election
- 1921 Northern Ireland general election
- 1921 Penistone by-election
- 1921 Penrith and Cockermouth by-election
- 1921 Southwark South East by-election
- 1921 Westminster Abbey by-election
- 1921 Woolwich East by-election