Yes. A TREC Amendment to Contract has to be signed by both the seller and the buyer to be considered executed. A one-sided signature doesn't count for anything — including preserving a deadline. TREC's guidance on repair amendments during the option period makes this explicit: a buyer-signed, seller-unsigned amendment at 4:55 PM on the option-expiry day is not an executed amendment.
The form itself is framed as a two-party agreement
The Amendment to Contract (currently TREC Form 39-11, effective 07/01/2026, replacing Form 39-10) is used to modify a contract that both parties already signed. The form's own opening language frames every change as something "Seller and Buyer amend the contract as follows" — not something either party can do unilaterally. The signature block at the bottom is where that gets made official: "EXECUTED the ____ day of ____________, 20____," with an instruction for the broker to fill in the date of final acceptance — the date the amendment actually becomes binding, distinct from when either individual party first signed it.
A signed-but-one-sided amendment isn't executed
This isn't just a formality — it has real consequences on a live deal. The clearest example comes from repair amendments negotiated during the option period: those have to be executed, meaning signed by both parties, before the option period expires in order to count. A buyer who signs their half but doesn't get the seller's signature back before the deadline hasn't actually locked anything in. A buyer-signed, seller-unsigned amendment sitting at 4:55 PM on the option-expiry day is not an executed amendment — it's just a proposal one side has agreed to.
Why this matters beyond repairs
The same logic applies to any of the ten types of changes the Amendment form covers — sales price, closing date, an additional option fee to extend the unrestricted right to terminate, a waiver of that right, or a changed financing-notice date. None of those changes are effective on the strength of one party's signature. If a deadline depends on an amendment being in place, don't treat a signature from only one side as good enough — confirm both signatures are back before you rely on it.
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Is a TREC amendment binding if only the buyer has signed it? +
No. An amendment isn't executed until both the seller and the buyer have signed. A one-sided signature doesn't make the change effective.
What's the risk of relying on a one-sided signed amendment near a deadline? +
If a right depends on the amendment being executed by a certain deadline — like a repair agreement before the option period expires — a signature from only one party doesn't preserve that right. The clock keeps running as if nothing was agreed.
Who fills in the execution date on a TREC amendment? +
The form specifically instructs the broker to fill in the date of final acceptance on the execution line at the bottom of the form, once both parties have signed.
Does this two-signature requirement apply to all ten types of changes on the Amendment form? +
Yes — sales price changes, closing date changes, additional option fees, waivers of the option right, financing-notice date changes, and everything else on the form all require both parties' signatures to be effective.
This page is provided as-is for educational purposes. It is not legal advice. Always verify deadlines and contract interpretations against your executed contract and confer with your broker or a Texas real estate attorney for binding interpretations. meetdossie.com