Wow, that was quick! I have been through the threads already and most seem to suggest something along the line of "acknowlegement of receipt" which appears to me accurate but not something you would actually say in English whereas Recorded Delivery is a common phrase. I just wondered if anyone else had used it in this context.
I have checked over the links, and I think your answer probably lies there. But I have the same problem you do. As an American, I would probably not say that. Instead, I would say "by certified letter".
-I just saw that you had already responded. I personally have never used 'recorded delivery', but that's probably a difference between American and British English.
You haven't actually *given* the context particularly - a bit more information might help us to sort out precisely what translation would be appropriate, because most of what people have said above could apply under certain circumstances.
Yes, that's exactly what it is, that's how it works in France, and the sender is then sent confirmation that the mail has been signed for. That I understand and know. What I don't know is how to put that in concise, unambiguous English (especially if the same service doesn't exist in the UK)!