From the text of the deal itself? All the nuclear restrictions were for "15 years", and some for 10 years. After that? Unclear.
Surprised at the downvotes - read the text for yourself: http://www.documentcloud.org/documents/2165388-iran-deal-tex... search for 15 years, it's the plain fact of the matter, not some "talking point".
They don't normally have a set end date.
A set end date basically means Iran plans to restart activities on that date without any kind of sanction. There's a reason this deal was so heavily criticized.