He is also far from achieving the lengthy stints of many living leaders, with Equatorial Guinea’s Teodoro Obiang Nguema the longest-serving president at 40 years.
Britain’s Queen Elizabeth II is the longest-reigning monarch at 67 years.
Putin first came to power as prime minister of Russia in 1999, being elected president the following year.
In 2008, after two presidential terms, he handed the role to Dmitry Medvedev and stepped back to become prime minister again.
He returned to the Kremlin in 2012, triumphing at the polls in 2018 for a fourth term as president.
To mark his 20 years in office, here are other world leaders who have managed to stay at the top for more than two decades.
Leading the pack is Cuba’s revolutionary hero Fidel Castro, with 49 years in power. When he handed over in 2008, ill and aged in his early 80s, it was to his brother Raul.
Taiwan’s first president Chiang Kai-shek was in charge on the island and in mainland China for a total of 47 years until his death in 1975.
North Korea’s founder Kim Il Sung ran the reclusive state for 46 years before dying in office in 1994, remaining revered as the “eternal leader”.
Moamer Kadhafi ruled Libya with an iron fist for almost 42 years but was ousted and then slaughtered in 2011 at the height of the Arab Spring uprisings.
Omar Bongo Ondimba governed oil-rich Gabon for more than 41 years until his death from cancer in 2009.
Albania’s communist dictator Enver Hoxha was in power for 40 years until he died in 1985.
Equatorial Guinea’s Obiang became the world’s longest-serving living leader on August 3, 2019, having siezed power in a 1979 coup.
Monarchs aside, others still adding up their time in the top job are:
– Cameroon’s President Paul Biya who has already ruled for 37 years
– Congo-Brazzaville’s Denis Sassou Nguesso now at 35 years, excluding a five-year pause after he lost a 1992 election
– Cambodian Prime Minister Hun Sen, 34 years
– Uganda’s President Yoweri Museveni, 33 years
– Iran’s Ayatollah Ali Khamenei has been supreme leader since the death of Ayatollah Ruhollah Khomeini in 1989
– Chad’s Idriss Deby Itno, 28 years
– Tajikistan’s Emomali Rakhmon, 27 years
– Eritrea’s Isaias Afwerki, 26 years
– Belarussian Alexander Lukashenko, 25 years
– Djibouti’s Ismail Omar Guelleh, 20 years
– Gabon’s Ali Bongo will have been in power for 20 years in October 2019.