How to Link a Battle.Net Account to Activision Account

If you play on Xbox or PlayStation

You must goto https://activision.com/
Login there using the Xbox or PlayStation logo
(Make sure to use the logo of the console you play on to sign in with. If you play on Xbox use the Xbox logo to sign in on Activision.com and if you play on PSN use the PlayStation logo to sign in on Activision.com)

Once signed in on Activision.com, click on profile (in the top right)
And link a Battle.Net Blizzard Account there. Once linked provide us the battlenet login email and password.

Everything should all show linked on that Activision profile page

If you don't have a Battle.Net Blizzard account already you can easily make one here.

Create BNet/Blizzard Account here: https://account.battle.net/

Everything should all show linked on the activision profile page like this (in the example below since we play on Xbox we logged in with the Xbox logo and linked a BattleNet):

Example in link below:
https://gyazo.com/64252d9b99f86d700681f6770ad84980