overseesguideline

Some of these people may be able to 'transit without visa' (TWOV) – see below for more details.
If you will be staying in the UK for up to 48 hours before you continue your journey, you will need a 'visitor in transit' visa. If you want to stay in the UK for longer than 48 hours, you will need to apply for a visit visa.
An Immigration Officer may decide to let you pass through the UK on your way to another country without holding a visa. This is known as 'transit without visa' (TWOV). It allows you to catch a connecting flight within 24 hours or, if you are on-board a ship, to stay at a UK port for up to 24 hours.
DATV nationals are visa nationals who must have a visa to pass through the UK on their way to another country, even if they are not entering the UK or changing airports. Unless they qualify for exemption from the DATV requirement, they cannot transit without visa (TWOV). (You can get more information about DATV exemptions below.)
Please use the “Direct Airside Transit Visa (DATV) nationals” link below to get a list of countries whose nationals need direct airside transit visas for the UK or contact our visa section for more details.
If you have a DATV, you will not be able to pass through UK Immigration Control, or collect any luggage on your journey through the UK. You will not usually be allowed to stay in the UK overnight to wait for a connection to continue your journey.

This will depend on how your nationality is described in your travel documents.
If you are a DATV national the Immigration Rules for DATV nationals apply to you and you will need a direct airside transit visa, unless you qualify for exemption.
If you are not a DATV national, the Immigration Rules for visa nationals apply to you and you will need a 'visitor in transit' or visit visa unless you qualify for transit without visa (TWOV).
If you are recognised as 'stateless' under the 1954 UN Convention relating to the Status of Stateless Persons, the Immigration Rules for visa nationals apply to you and you will need a 'visitor in transit' or visit visa unless you qualify for transit without visa (TWOV).
Holders of valid non-national travel documents issued by the UK do not need a UK visa to pass through the UK on their way to another country.
Transit by sea and land:

to the Republic of Ireland, the Channel Islands or the Isle of Man.
If you are a visa or DATV national passing through the UK by sea and land on your way to the Republic of Ireland, the Channel Islands or the Isle of Man, you will need a visit visa for the UK.
from the Republic of Ireland, the Channel Islands or the Isle of Man.
If you are a visa or DATV national passing through the UK by sea and land on your way from the Republic of Ireland, the Channel Islands or the Isle of Man to another country outside the UK, you will need a visitor in transit or visit visa for the UK.

Transit by air to and from the Republic of Ireland, the Channel Islands or the Isle of Man

If you are a visa national or an exempt DATV national passing through the UK by air on your way to or from the Republic of Ireland, the Channel Islands or the Isle of Man, you may qualify for transit without visa.
If you are a DATV national passing through the UK by air on your way to Ireland, the Channel Islands or the Isle of Man, you will need a visit visa for the UK.
If you are a DATV national passing through the UK by air on your way from Ireland, the Channel Islands or the Isle of Man to another country outside the UK, you will need a visitor in transit or visit visa for the UK.

You will be exempt from the DATV requirement and may be able to transit without visa if you hold one of the following.

A valid visa for entry to Australia, Canada, New Zealand or the United States of America and a valid airline ticket for travel through the UK as part of a journey from another country or territory to the country for which you have the entry visa.
A valid visa for entry to Australia, Canada, New Zealand or the United States of America and a valid airline ticket for travel through the UK as part of a journey from the country for which you have the visa to another country or territory.
A valid airline ticket for travel through the UK as part of a journey from Australia, Canada, New Zealand or the United States of America to another country or territory, as long as you do not transit (pass through) the UK on a date more than six months after the date on which you last entered Australia, Canada, New Zealand or the United States of America with a valid visa for that country.
A valid USA I-551 permanent resident card issued on or after 21 April 1998.
A valid Canadian permanent resident card issued on or after 28 June 2002.
A valid common format category D visa for entry to an EEA state – see our 'EEA and Swiss nationals' leaflet for a list of EEA states.
A valid common format residence permit issued by an EEA state under Council Regulation (EC) number 1030/2002.
A diplomatic or service passport issued by the People’s Republic of China.
A diplomatic or official passport issued by India.
A diplomatic or official passport issued by Vietnam.

Notes on DATV exemptions

A valid US immigrant visa packet (form 155A/155B) is a 'valid visa' for DATV exemption.
If you have an expired I-551 permanent resident card issued on or after 21 April 1998 with an I-797 extension letter issued by the Bureau of Citizenship, you do not need a DATV.
If you have either:

an I-512 parole letter or an I-797C (notice of action) instead of a valid US visa; or
a transportation letter instead of a valid US permanent resident card issued on or after 21 April 1998;

you are not exempt and need a DATV.

If you hold a valid travel document with a US ‘ADIT’ stamp saying – 'Processed for I-551. TEMPORARY EVIDENCE OF LAWFUL ADMISSION FOR PERMANENT RESIDENCE VALID UNTIL [date]. EMPLOYMENT AUTHORIZED', you are not exempt and need a DATV.

Whether holders of non-national (including refugee) travel documents require a DATV depends on their nationality and whether they qualify for one of the exemptions listed above. So, for instance, the holder of a non-national travel document (such as a refugee travel document) who is a national or a citizen of one of the countries listed on the DATV list (for example, Afghanistan) will need a direct airside transit visa (DATV) if they are travelling to the UK in transit to a third country.

If you are a visa national or a DATV national who is exempt, you can transit without visa if you will:

arrive at a UK port on a ship and leave on the same ship within 24 hours; or
arrive and leave by air within 24 hours and have no intention of staying in the UK (you can travel by rail or road between two airports); and
have a confirmed onward booking that will leave within 24 hours of your arrival in the UK.

You must also have the documents you need:

to enter the country you are travelling to; and
for any other country that you may pass through on your journey.

If you want to apply for a visitor in transit visa, you must be able to show that you:

have the necessary visa for the country you are travelling to;
are travelling to a country outside the UK, the Channel Islands, the Isle of Man or the Republic of Ireland;
can and intend to go straight to another country;
will be allowed entry to that country; and
qualify for entry as a visitor (read our 'Visitors' guidance for more information).

You will need to fill in a visa application form.
You must apply for your visa in the country of which you are a national or where you legally live.
You can apply in a number of ways, for example by post, by courier, in person and online. This website will tell you about the ways in which you can apply.
Your visitor in transit visa will usually be valid for six months. You can use it to travel through the UK as many times as you like during that time, as long as your passport and visa for the country that you are travelling to are still valid. The visa will only be valid for entry to the UK if you meet these conditions each time you travel through the UK.

If you want to apply for a DATV you will need to show that you:

have booked an onward ticket from the UK for travel within 24 hours of your arrival;
will not need to change airport in the UK;
have all the correct documents you will need to be allowed to enter the country you are travelling to; and
will not need to pass through the UK's immigration control.

You will need to fill in a visa application form.
You must apply for your visa in the country of which you are a national or where you legally live.
You can apply in a number of ways, for example by post, by courier, in person and online. This website will tell you about the ways in which you can apply.
Your DATV will usually be valid for six months. You can use it to travel through the UK as many times as you like during that time, as long as your passport and visa for the country that you are travelling to will still be valid after the transit visa runs out. The visa will only be valid for entry to the UK if you meet these conditions each time you travel through the UK.