Many couples choose to do the legal part of the wedding or civil partnership in this country and have their celebratory ceremony abroad. A formation of marriage or civil partnership abroad is conducted according to the law of that country.
If you wish to get married or form a civil partnership abroad, you must consult the authorities of the country where the event will take place.
They may ask you to provide a certificate of no impediment. This may be obtained by giving notice of your intention to marry or form a civil partnership at your local registration office [GOV.UK]. It is your responsibility to check the information you provide to the registrar is correct.
The certificate of no impediment can be issued 28 days after giving notice
You will need to check with the authorities of the country of marriage or civil partnership as to the required validity period of the document.
For more information, contact that country's embassy [GOV.UK].