The ID is unique and every company account on LinkedIn has one. There are a few ways to find your company's LinkedIn ID.
Via the Jobs page.
Go to your company's LinkedIn page (for example https://www.linkedin.com/company/whoco).
Select the Jobs tab and then select "see all jobs"
Go to the URL. The company ID is the value after 'f_C=<numeric value>&' so for an example the company ID in the example below is 19071805
Via the Admin page.
To find your LinkedIn company ID as a LinkedIn Page Admin, navigate to the Admin View of the LinkedIn Page from the All Pages or Home tab. The LinkedIn company ID is the numbers after "/company/" in the URL.
Updated on: 22 / 10 / 2021