AWS owns roughly $2B worth of IPv4 addresses

Or more ? $7 USD / month per running instance $86 USD / year

How much do Elastic IPs cost? Elastic IPs are totally free, as long as they are being used by an instance. However, Amazon will charge you $0.01/hr for each EIP that you reserve and do not use. You will be charged if you ever remap an EIP more than 100 times in a month.