How to Steps:
From your Square Dashboard Home screen, click on Account Settings
On the left side Menu Bar, click to expand the Category: Business Information
Click on Locations
Click on the Name of the Location and it will take you to the page Location Details
In the Address Bar of your Browser at the top of your screen, you'll see https://squareup.com/dashboard/locations/ + a series of number and letters
The numbers and letters following /locations/ is you Square Location ID. Copy this portion
For example:
FAQ:
Q: What format does my Square location ID come in?
A: It will be a series of letters and numbers that appear in your address bar when viewing Location Details in your Square dashboard. for example: LJVHEE61K6WT9