Board Thread:Lore Discussion/@comment-28157605-20160704151728/@comment-34660304-20170308153925

Elves are able to live up to hundreds or even thousands of years. Divayth Fyr for example was 4000 years old during the events of Morrowind. Knight-Paladin Gelebor was said to have already matured during The Return, although this could also be the case of Auri-El's protection in the Chantry.

Humans generally have the same life expectancy like real-life humans did in the Middle Ages. Which means they tend to age until 60 - 70 years I believe.

Bretons are a rare case. Since their ancestors gradually interbred with Mer, I believe that they are able to live longer than their human cousins, but less than their Elven cousins. I think they share approximately the same characteristics like the Dunedain in Tolkien's Legendarium, who were able to surpass the age of hundred.

As for beastfolk, I am not sure. I've never heard of any Argonian or Khajiit ever reaching immortality (excluding the Nerevarine of course). Dragons are immortal but as always, they are a rare case.