To see how many ad account you can have in your Facebook Business Manager:

1.  Go to https://business.facebook.com/

2.  Select the Business

3.  On the next page click the square fly-out menu in the left nav and then click on Business Settings

Next, in Facebook Business Settings go to Business Info towards the bottom of the left nav and you will see your ad account limit at the bottom of the Business Details section

Back to the 👉 Facebook Business Manager Guide