← 1819 1818 1817 1820 in Denmark → 1821 1822 1823
Decades:	1800s 1810s 1820s 1830s 1840s
See also:	Other events of 1820 List of years in Denmark

Events from the year 1820 in Denmark.

Incumbents

• Monarch – Frederick VI^[1]

Events

• 1 May – Sparekassen for Kjøbenhavn og Omegn is established in Copenhagen.

Undated

• Bella and Hanna. The Eldest Daughters of M. L. Nathanson is painted by Christoffer Wilhelm Eckersberg

Births

January–March

• 28 January – Vilhelm Pedersen, artist, illustrator (died 1859)

October–December

• 2 October – Georg Petersen, businessman (died 1900)<ref"Georg Petersen". Dansk Biografisk Leksikon (in Danish). Retrieved 16 June 2022.</ref>
• 25 October – Lorenz Frølich, painter (died 1908)
• 26 November
  • Prince Frederick William of Hesse-Kassel (died 1884 in Germany)
  • Johan Adam Schwartz, turner (died 1874)

Deaths

January–March

• 1 March – Peter Christian Uldahl, piano maker (born 1779)

April–June

• 13 April – Johan Ludvig Mansa, landscape architect (born 1740)
• 19 April – Johan Ludvig Mansa, landscape architect (born 1740 in Zweibrücken)
• 27 May – Jean-Françoìs de Dompierre de Jonquières, merchant, landowner and amateur artist (born 1775)

July–September

• 30 July – Carl Adolph Castenschiold, landowner and chamberlain (born 1740)

October–December

• 26 December – Frederik Ludvig Bang, physician (born 1747)