Meta Business Help Centre
About buying ads for business purposes

Whether you're using Meta ads for business purposes or private, non-business purposes determines whether and how value-added tax (VAT) and goods and service tax (GST) are assessed.
Almost all advertisers use Meta ads for a business purpose. If you seek to use Meta ads to get any economic advantage by promoting goods or services, then you're using Meta ads for business purposes. This includes affiliates, sole traders, self-employed merchants, partnerships and other situations.