In practice, almost nothing. "NDA" (Non-Disclosure Agreement) and "confidentiality agreement" describe the same legal instrument — a contract where one or both parties agree to keep certain information private. Lawyers, business owners, and HR departments use the two terms interchangeably, and courts treat them identically.
The more useful question is usually not "NDA vs. confidentiality agreement?" but rather "one-way vs. mutual?" or "what should actually be in this document?" Those distinctions actually matter.
"NDA" is the American vernacular term — dominant in startup culture, tech, and entertainment. "Confidentiality agreement" is favored in more formal or traditional legal contexts (employment law, M&A, healthcare). In the UK and Commonwealth countries, the preferred term is "confidentiality agreement" or "CA." The European business world often uses "NDA" as borrowed Americanism, or "CA" in formal documents.
Sometimes you'll see "Proprietary Information Agreement" (PIA) or "Non-Disclosure and Non-Use Agreement" — these are still the same thing, sometimes with a broader scope that explicitly covers not just disclosure but use of the information. The label on the document doesn't determine its legal effect. The substance does.
Only one party discloses; only the other is bound to keep it confidential. Common when: an employee joining a company, a vendor accessing your systems, an investor reviewing your financials before they commit anything.
Both parties share information; both are bound. Common when: two companies exploring a partnership or acquisition, two founders discussing a joint venture, a discovery process where both sides need to show their cards.
Which you need depends on who's sharing what. If information only flows one direction, a one-way agreement is cleaner and puts the obligation clearly on the party receiving your information. Mutual agreements are appropriate when both sides have something to protect.
One thing that is different: a standalone confidentiality agreement vs. a confidentiality clause inside a larger contract. Many service agreements, employment contracts, and partnership agreements contain a confidentiality section that does the same job as a standalone NDA. You don't always need a separate document — if the larger agreement already has a solid confidentiality clause, an additional NDA may be redundant.
The advantage of a standalone NDA is clarity and timing — you can sign it before you've finalized the main agreement, giving you protection during the negotiation phase itself.
In employment law, "non-disclosure agreement" can sometimes be a term of art that encompasses non-disparagement clauses, non-compete provisions, or other restrictive covenants. Some states have passed laws restricting the use of NDAs specifically in sexual harassment settlements. In those contexts, the label on the document matters because the law uses the same label.
If you're dealing with an employment settlement or a situation that might fall under state NDA restrictions, get a lawyer to review the specific document rather than relying on the general "they're the same" answer.
filefriend is a software tool, not a law firm. This article is general information, not legal advice. For high-stakes or employment-related NDAs, consult a lawyer.