Silver pieces weighing 7.78g or more must be hallmarked. I am registered with the Edinburgh and London Assay Offices and from 2026 any of my pieces requiring a hallmark will bear the Edinburgh marks. Smaller pieces currently in circulation that are under this weight still bear my Makers Mark as registered with the London Assay Office.
Click on the link which will give you some hallmarking details as provided by the London Assay Office.