Can a contractor register a lien against a condominium unit in Ontario?

Yes, but where the lien attaches depends on who the contractor actually did the work for. A contractor hired directly by a unit owner to renovate or improve their specific unit can generally register a lien against that individual unit's title for unpaid work. Work done on the condominium's common elements, however - the building envelope, shared systems, or common area improvements - generally results in a lien against the condominium corporation's interest or the common elements generally, rather than against any one owner's individual unit, since it's the corporation, not an individual owner, that typically contracts for that kind of work.

This distinction matters because it determines who the lien claimant needs to pursue and what's actually at risk - an individual owner facing a lien tied only to their own unit's renovation is in a very different position than a condo corporation facing a lien related to a building-wide project affecting every owner's common expenses. Because condominium projects often involve multiple contracts and funding sources, correctly identifying who contracted for the specific work in dispute is usually the first step in figuring out where a lien properly attaches.