You can check out the official government website: Come to the UK to get married - GOV.UK (www.gov.uk) If you need details specific to the Canadian connection, maybe give the UK embassy in Canada a visit at https://www.gov.uk/world/organisations/british-high-commission-ottawa

 

I provided a response here: https://www.easyexpat.com/forums/t/getting-married-in-uk-to-a-canadian.60324/#post-113736

 

I saw @Jamie already provided a really helpful and detailed response breaking down everything you need to know about getting married in the UK as a Brit/Canadian couple. Definitely check out the government website for official guidance as well. Sounds like as long as your fiancé meets the visa requirements for a short visit, it should be a pretty straightforward process. Best of luck with all the wedding planning!