What happens if I restore my iPhone 4S? Will it erase everything including voice mails?

What happens if I restore my iPhone 4S? Will it erase everything including voice mails?

This depends on if you have icloud set up with the phone, usually you won't because everything even apps if icloud is turned on will save everything and just redownload it. May i ask why you are restoring it?

Everything on the phone yes would be deleted. Voicemails, no since that is more related to the carrier not the phone.