Ask HN: Best way/service to Fax something online in UK

I am in the UK and need to fax (yes, i know) some documents to another number in the UK (their requirement).

Has anyone done this recently, what would you recommend, given that we are no longer living in the pre-2000s?

There are various options online that offer such services, but perhaps there is a better, or best way to do this without all the marketing landing pages.