Certification process
A marriage / civil partnership certificate is a UK public document, so it can go straight to the Foreign, Commonwealth & Development Office (FCDO) for the apostille certificate.
Document requirements
Register-office or GRO issue; original only.
Digital e-Apostille
No — the FCDO does not issue an electronic e-Apostille for a marriage / civil partnership certificate, so this needs the paper apostille.
The Hague Convention
An apostille authenticates a UK public document for use in countries that are members of the Hague Apostille Convention. Destinations outside the convention may need further embassy legalisation instead.