Tip! If you do not have CRA my individual account, please create it first [https://drive.google.com/file/d/1V7koikAO4aalh83bsH701pe7PlQTuO8j/view?usp=sharing](https://drive.google.com/file/d/1V7koikAO4aalh83bsH701pe7PlQTuO8j/view?usp=sharing)
Go to [https://www.canada.ca/en/revenue-agency/services/e-services/e-services-businesses/business-account.html](https://www.canada.ca/en/revenue-agency/services/e-services/e-services-businesses/business-account.html) and click on sign in Enter your personal CRA id and pwd.
Click "Add a business"
Enter second company business number and press Add.
Alert! At times It might say here that you are not primary person for business and screen will give error message and give you phone number for CRA. If this comes up, please call CRA my business on given number and tell them over call "I am primary owner" So CRA will fix it from their side.\ \ Once that is done, you can add your business by coming here again.