Does the operator in an HST joint venture election have to be one of the co-owners?

Generally, yes, the operator designated under a joint venture election is typically expected to be one of the actual co-venturers in the joint venture, or in some structures, an eligible entity closely tied to the venture that meets specific conditions, rather than an unrelated third party being brought in purely to handle the paperwork. The rules are built around the operator being a genuine participant with a real stake in, and knowledge of, the joint venture's activities.

This matters when co-owners are considering bringing in an outside property manager or administrative service to handle HST filings, if that manager isn't itself a co-venturer and doesn't meet whatever specific conditions might allow it to be named operator, using it as the designated operator for the election may not be valid, even if it's doing the practical bookkeeping work day to day. There's a difference between who administers the paperwork behind the scenes and who is legally the designated operator for GST/HST purposes.

Because using the wrong entity as operator can mean the whole election is invalid, putting the co-venturers back to filing individually and potentially exposed for tax that wasn't properly accounted for, confirm with a tax advisor exactly who can be validly named operator for your specific joint venture structure before filing the election.