I hope to seek some advice on marrying my partner who is from South Africa. We have been together 2 years and she has visited me twice in the UK where I am born and lived my whole life. Am I allowed to marry her now whilst she is here but she is only on a visitor visa and I want to surprise her.
No. Marrying, registering a civil partnership, or giving notice of marriage or civil partnership is not permitted for those visiting the UK on a Standard Visitor visa https://www.gov.uk/standard-visitor-visa Edit: this Can I marry in the UK while on a standard visitor visa? provides a huge amount of detail on the topic