Visa requirements for British citizens

Visa requirements for British citizens are administrative entry restrictions by the authorities of other states placed on citizens of the United Kingdom. British citizens had visa-free or visa on arrival access to 187 countries and territories, ranking their passport 7th in terms of travel freedom (tied with Belgium, New Zealand, Norway, Switzerland and the US) according to the Henley Passport Index. Additionally, the World Tourism Organisation also published a report on 15 January 2016 ranking the passport 1st in the world (tied with Denmark, Finland, Germany, Italy, Luxembourg and Singapore) in terms of travel freedom, with the mobility index of 160 (out of 215 with no visa weighted by: 1, visa on arrival weighted by 0.7, eVisa weighted by 0.5 and traditional visa weighted by 0).
Visa requirements for other classes of British nationals such as British Nationals (Overseas), British Overseas Citizens, British Overseas Territories Citizens, British Protected Persons or British Subjects are different.
History.
Visa requirements for British citizens were lifted by many European nations in the few years after World War II. The first changes occurred in 1947. These were removed by France on 1 January 1947.
This was then quickly followed by Belgium on 15 February 1947, Luxembourg 15 February 1947, Norway on 1 March 1947, Denmark on 22 March 1947, Sweden on 1 April 1947, Netherlands on 15 April 1947, Switzerland on 24 June 1947 Liechtenstein on 24 June 1947 and Iceland on 1 July 1947.
The requirement was lifted by Italy on 1 January 1948, Monaco (8 November 1948), Austria (15 May 1955), Paraguay (27 November 1966), United States (1 July 1988), Poland (1 July 1992), Bulgaria (March 1997), Romania (1 January 2001), Serbia and Montenegro (31 May 2003), Ukraine (1 May 2005), Georgia (1 June 2006), Moldova (1 January 2007), Kyrgyzstan (27 July 2012), Armenia (10 January 2013), Kazakhstan (15 July 2014), Indonesia (13 June 2015), Vietnam (1 July 2015) Belarus (12 February 2017), Cape Verde (1 January 2019), Uzbekistan (1 February 2019), Turkey (2 March 2020), Oman (December 2020), countries in the Schengen Area (1 January 2021), Bulgaria (1 January 2021) and Romania (1 January 2021). 
Electronic visas for British citizens were introduced: India (15 August 2015), Djibouti (18 February 2018) and Malawi (October 2019).
Visas on arrival have been waived for British citizens by Mali (March 2015) and were for Malawi (1 October 2015 for four years, see above).
Visa-free travel to Ukraine is temporary until 30 January 2022.
Common Travel Area.
The United Kingdom, together with its Crown Dependencies of Guernsey, Jersey and the Isle of Man and the Republic of Ireland make up a Common Travel Area where:
However, there are occasionally checks on coaches and trains moving between Northern Ireland and the Republic of Ireland. British citizens living in Ireland have many of the same rights and entitlements as an Irish citizen. Citizens of third countries must have passports and, if required, visas to travel between the United Kingdom and Republic of Ireland.
British visas don't enable travel to Ireland for people without agreement with Ireland, and vice versa. Passengers travelling between the Common Travel Area and the Schengen Area are subject to systematic passport/identity checks.
Visa requirements.
This table documents the visa requirements, and not travel restrictions related to the COVID-19 pandemic.
Non-ordinary passports.
Holders of exclusive categories of British passports have this visa-free access, to: China , Kuwait , Mongolia , Qatar and the United Arab Emirates . Holders of diplomatic or service passports of any country have visa-free access to Ethiopia, and Zimbabwe. Holders of British official and diplomatic passports require a visa for South Africa.
Non-visa restrictions.
Travel restrictions related to the COVID-19 pandemic.
Due to the COVID-19 pandemic, several countries have imposed temporary travel restrictions on British citizens or persons arriving from the United Kingdom.
Travel impact of Brexit.
On 23 June 2016, a majority of the British electorate voted to leave the European Union in a nationwide referendum. In March 2017, the UK sent notification of their intention to leave the EU to the European Council through Article 50 of the Lisbon Treaty. British citizens will cease to be EU citizens upon the UK's departure from the EU. The UK withdrew from the EU on 31 January 2020, but British citizens retained the right of freedom of movement until the transitional period ended on 31 December 2020.
From 1 January 2021, when EU law ceased to apply to the United Kingdom, British citizens are afforded visa-free visits to the Schengen Area, for 90 days in any 180-day period. British citizens also enjoy visa-free entry to Bulgaria and Romania. 
From sometime in 2022, most visa-exempt aliens seeking entry to the EU and EEA must apply and pay for travel authorisation through ETIAS. This was confirmed on 12 September 2018 and has no exception, yet agreed, for British citizens. This excludes British-Irish travel which is governed by laws that pre-date the European Community.
When in a non-EU country where there is no British embassy, British citizens no longer have the right to get consular protection from the embassy of any other EU country present in that country.
Consular protection of British citizens abroad.
When in a country where there is no British embassy, British citizens may get help from the embassy of any other commonwealth country present in that country. There are also informal arrangements with some other countries, including New Zealand and Australia, to help British nationals in some countries.
See also List of diplomatic missions of the United Kingdom