As of October 29th 2018 a new set of visa regulations applies to all British citizens travelling to Turkey. If you're heading to any Turkish destination on business or pleasure, you now need to arrange your e-visa prior to travel, you will no longer be able to pick one up on arrival at the airport.
Turkey's new visa entry requirements
All British nationals require a visa to gain entry into Turkey. The only exception is those travelling to Turkish sea ports via the likes of cruise ships who, providing they stay in the country no longer than 72 hours, may not need to apply.
The British Foreign Office website has updated their travel info warning Brits to only arrange visas via official channels and the Republic of Turkey e-Visa website. Internet searches bring up a number of unauthorised websites. As the UK Foreign Office warns, "be wary of such sites and businesses, particularly those that seek additional fees for other services. Some unauthorised websites have issued fake e-visas". The official Turkish e-visa application is a simple 3-step process online. It costs $20 per person. The visa can be applied for up to 3 months prior to arrival in Turkey and allows multiple visits up to a total of 90 days in a 180 days period. If you are intending to stay longer, different visa rules apply. To stay more than 3 months, a 'Short Term Residence Permit' should be applied for either from the Provincial Directorate of Migration Administration during your stay in Turkey, or before travelling to the country (rules and regulations do apply). For more information please see the Turkish Ministry of the Interior website.
Once you have applied and been granted your e-visa, download it and print off a copy to take with you in case you run into any issues at Turkish passport control. It's also a good idea to have a copy saved on your phone.
Visas for those with "UK Special Passports".
For 'British Subjects', 'British Nationals (Overseas)', 'British Protected Persons' and others that don't hold a traditional 'British Citizen' passport, visas to Turkey need to be applied for through the Turkish Consulate General in advance of travel to the country.
Other passport requirements for entry to Turkey
Those travelling to Turkey should ensure there is at least 6 months validity remaining on their passport, they should also check there is sufficient room left on a page in the passport for a visa stamp. Those travelling with duel Turkish / British nationality children should also take with them an official document stating that both parents have granted permission for the child to travel (officials often ask for proof of parental consent to travel abroad). Those travelling with UK emergency travel documents should be granted entry and exit providing the dates fall in line with those stated on official documents.
If you require any further information on the Turkish visa regulations, please refer to The Republic of Turkey Ministry of Foreign Affairs official website.