「歳」と「才」の差異

Two different kanji to express age: 「歳」 and 「才」. Both are read さい and one is a heck of a lot easier to write (hint: which one is ２年生漢字?) I've noticed 歳 is much more common, but 才 is coming up a lot more in my readings lately. Is there any guidelines as to which one you should use, or is it just a matter of personal preference?

ありがとう。

The easy one is just a simplified character. They mean the same thing. You should be able to read both, but if you are only able to write 才, that's fine. Personally, I learned 歳 first, so I tend to use that. For personal correspondence, it's probably more a matter of preference and convenience, in which case 才 is more common.

Thanks for the answer. Nice Gaijin indeed.