Does an NDA need both signatures?
Not always as a matter of law, but almost always in practice. A contract needs both sides to agree, and signatures are the clearest proof that they did. A one-way NDA is sometimes signed by the recipient alone; a mutual NDA should carry both. Here is why, and what to do when the countersigned copy never arrives.
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Open the NDA you were sent, sign it as yourself or for your company with name, title and date, and send it back. The PDF stays on this device the whole time.
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Updated 28 September 2026 · Written by Joe Farwick, who runs this site
Why signatures matter for an NDA
A contract exists when the parties agree to the same terms. Courts look at outward expressions of that agreement, typically an offer and its acceptance, rather than at what anyone privately intended. A signature is the most common and convincing expression, but in general it is evidence of agreement rather than a magic ingredient. That is why the honest answer to “is an NDA valid with one signature?” is “it depends”.
It depends, first, on the NDA itself. Many NDAs say they take effect when signed by both parties, or that they are binding only once executed by each party. If yours has such a clause, a single signature means there is no agreement yet. It depends, second, on the governing law. In US states, the statute of frauds requires certain contracts, including those that cannot be completed within one year, to be in writing and signed by the parties they bind. Whether a multi-year NDA falls under that rule depends on the state and on the wording, and it is one more reason to hold a copy signed by the party you may need to enforce it against.
One-way NDAs: the recipient's signature is the important one
In a one-way NDA only the recipient promises to keep information confidential, so the recipient's signature is what the discloser needs. That is why reception-desk NDAs and some candidate NDAs are signed by the visitor alone. The discloser's signature still helps: it shows the discloser accepted the same purpose, duration and exclusions, which matters if the recipient later relies on those limits.
If you are the recipient and the discloser does not sign, you are still expected to keep your promise. Keep a copy of what you signed and the email you sent it with, so you can show which version you agreed to.
Mutual NDAs: get both signatures before sharing
In a mutual NDA each side promises to protect the other's information. If only you sign, you have committed yourself while the other side's commitment is uncertain. The practical rule is simple: do not share your own confidential material until the countersigned NDA is back. If a meeting cannot wait, ask the other side to confirm by email, before the meeting, that it accepts the NDA as sent; that email is far better evidence than a recollection of a phone call.
What if the other party never countersigns?
Chase once, politely, with the PDF attached again. If the other side has already shared information or acted on the NDA, it may be possible to argue that it accepted the terms by its conduct, but that is exactly the kind of argument a signature avoids, and it cuts both ways. Until you have a countersigned copy or a clear written acceptance, treat the NDA as not yet agreed for your own information and as binding on you for what you received.
If the other side wants changes instead of signing, you have a negotiation rather than an NDA. Agree the final wording, then both sign that version; do not leave a signed earlier draft in circulation.
Who signs first, and which date counts?
It does not matter legally who signs first. Usually the party that drafted the NDA sends it for signature, the other signs and returns it, and the drafter countersigns. If the NDA has no fixed effective date, it commonly takes effect on the date of the last signature, so make sure both signature blocks are dated. When you add your countersignature in NDAPDF, you work on the PDF the other side sent, sign your own block, add the date, and return the completed file.
Situations and what they usually mean
Visitor or candidate NDA
Often signed only by the visitor or candidate; the company's promise is minimal.
One-way NDA for a pitch
The recipient's signature is what matters, but a discloser signature removes doubt.
Mutual NDA
Both sides take on duties, so both signatures should be on it before secrets move.
“Binding when signed by both”
If the NDA says so, one signature is not enough, whatever else happened.
Signed in counterparts
Two identical copies, each signed by one party, together count as one agreement.
No countersignature, info shared anyway
Conduct may show agreement, but that is an argument, not a record.
Getting a fully signed NDA
The order does not matter much; ending up with both signatures does.
1
First signature
One party signs its block and sends the PDF to the other.
2
Countersignature
The other party signs its block on the same PDF and returns it.
3
Both keep it
Each side stores the copy with both signatures, dated.
Signature questions
Is an NDA signed by both parties?+
A mutual NDA normally is, because both sides make promises. A one-way NDA is often signed by both too, but sometimes only the recipient signs, for example a visitor NDA.
Is an NDA valid if only one party signs it?+
Sometimes. If the NDA says it binds only once both sign, it is not. Otherwise agreement can be shown in other ways, but a single signature leaves room for argument.
Can we sign on separate copies?+
Yes, if the copies are identical. Signing in counterparts is common, and many NDAs say expressly that separately signed copies form one agreement.
Do I need to initial every page as well?+
Only if the NDA or the other side asks for it. Initials on each page help show that no page was swapped, and they are common in some countries.
What does countersigning an NDA on NDAPDF cost?+
Adding your countersignature is free to try. The fully signed PDF can be downloaded on a plan at €2.99 a month or €24.99 a year; cancelling stops the next renewal and leaves you access until the current period ends.
Countersign the NDA
Open the PDF the other side signed, add your signature and date in your block, and send it back.
Open the NDA