Is https://appleid.apple.com a legit website

The displayed website address is, but the one the link is actually to probably isn't. Don't submit any personal information there.

(149445)

Have to agree with Neil.

The address https://appleid.apple.com is a real Apple website for managing your Apple ID.

However, the E-mail is fake, as Apple will always address you by the name you have on file with them, and never as Dear Customer.

The underlying link in the mail may very well be sending you to a different place altogether, to phish out your Apple ID and password.

Also, a real email from Apple will specifically request you change your password, not update your information.

for clarification I now agree with Niel, I'm just showing the OP what the Apple one looks like. I was not clear.

No, it's not. An email which actually came from Apple will have the recipient's name instead of Customer in the first line; the email posted is otherwise very similar to a real one.

(149447)

the last one I got from Apple looked like this:

yes, it's from Apple

someone, possibly even you signed into iCloud with your account on a iPhone or iPad using iOS 10.0.3 for the first time on that device.

I have a real one as well. They'll have the recipient's name in the first line; ones with only 'Customer' are fake.

(149448)