Substantial Completion
The point when the project is usable for its intended purpose.
What it means
Substantial completion is the milestone when construction is sufficiently finished that the owner can use the project for its intended purpose, even though minor punch-list items remain. It is one of the most consequential dates in a construction contract: it commonly starts warranty periods, stops liquidated-damages exposure for delay, triggers retainage release timelines, and shifts responsibility for the property.
Why it matters before you sign
So much money and risk pivots on this one date that its definition — and who gets to certify it — deserves a careful read before you sign.
In a contract, it looks like this
The architect certified substantial completion on June 12, starting the one-year warranty period and the release of retainage.
This definition is a general, educational explanation — not legal advice. XOsign provides AI-assisted document tools and does not provide legal advice; consider consulting a qualified attorney for guidance on your specific situation. Requirements vary by state.
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