Ownership of advertising accounts is a question most companies address only when they change agency – and by then it is usually too late. What matters is whose account it was originally set up under. If a Google Ads or Meta account was created by the agency under its own management structure, it keeps it, together with the entire history of campaigns, conversion data and audiences built up over years, once the cooperation ends. The new supplier then starts from zero, and the algorithms have to learn all over again. The correct setup is simple: the company sets up its own Business Manager and its own ad account under its own company ID, and grants the agency only administrator-level access, which can be revoked at any time. The same applies to analytics, the tag manager, the domain and billing details. We recommend keeping a list of all accounts stating the owner and administrator as part of the contract.
See also: Ownership of the website and source code, Contract with a marketing agency, Digital Assets of a Company.
