For Scandinavians (from the Vietnam embassy website in Stockholm):
Citizens of Sweden, Finland, Denmark and Norway will be exempted from entry visa to Vietnam if:
- The intended period of stay is up to 15 days;
- The travelers hold valid passports of the above countries, with validity of at least 3 months from the intended date of entry into Vietnam;
- The traveler possesses, and could present upon request, a valid outbound ticket from Vietnam within 15 days of the arriving date;
- The traveler has not been banned from entering Vietnam.
As for UK passport-holders: I looked at the Vietnamese Embassy page in UK. You need a visa.
Curiously... for some reason it seems necessary for them to point out the following in the list as to visa-application:
"Abusive language and behaviour towards the Embassy's staff will not be tolerated and will affect the applications of the persons concerned." It seems there are some hot-headed Brits around, frequently enough for the embassy to need to point this out. :D
The info on what you need, can be found on the VN embassy page for UK:
www.vietnamembassy.org.uk/consular.html#VISA
But notice... the legalities may be different when applying for the visa from China, even though you are UK citizen. But this gives you the grit of what you need.
Hope it helps.