To draft an affidavit, put the court’s case caption at the top, identify yourself as the affiant, lay out the facts in numbered first-person paragraphs based on what you personally know, attach any supporting documents as labeled exhibits, and then sign the document in front of a notary who completes the jurat. In federal cases and many state matters, you can skip the notary by using a written declaration under penalty of perjury instead. Everything you write is sworn, and a false statement can carry up to five years in federal prison.1Office of the Law Revision Counsel. 18 USC 1621 – Perjury Generally
What Belongs in the Document
The Case Caption
The top block of the affidavit identifies the case it belongs to: the court’s name, the parties’ names, and the case or docket number assigned when the action was filed. If you have any prior filing from the same case, copy that caption exactly. Clerks match documents to files by the caption, so an inconsistency here can send your affidavit into the wrong pile.
Introducing Yourself as the Affiant
Right after the caption, state your full legal name, that you are over 18 and competent to testify, and that the facts to follow are true and within your personal knowledge. The traditional opener is: “I, [Full Name], being duly sworn, depose and state as follows.” That language is what turns the pages that follow from a written account into sworn testimony.
Numbered Statement of Facts
The body of the affidavit is the facts themselves, one to a numbered paragraph, written in the first person (“I saw,” “I received,” “I signed”). Put events in chronological order so a judge reading cold can follow the timeline without doubling back.
Exhibits
If documents back up what you are saying, attach them as exhibits and label them sequentially: Exhibit A, Exhibit B, and so on. Reference each one inside the numbered paragraph it supports. A standard phrasing is: “Attached as Exhibit A is a true and correct copy of the lease agreement dated January 5, 2026.” That sentence formally pulls the document into your sworn statement instead of leaving it as a loose attachment. Contracts, photographs, emails, medical records, receipts, and police reports are all common. Place the exhibits behind the signature and notary pages, each behind a cover sheet showing its letter. For long documents, tab or highlight the relevant portion so the judge is not hunting.
Signature Block and Jurat
Close with two sections. The signature block has a signature line, your printed name below it, and a date. Leave it blank for now; you sign in front of the notary. The jurat is the notary’s section, typically reading “Sworn to and subscribed before me this ___ day of _______, 20__,” with space for the notary’s signature, printed name, commission expiration, and seal. Many courts publish standard jurat wording or a fill-in affidavit form. If yours does, use it.
Format the whole thing cleanly: a centered title in capitals (“AFFIDAVIT OF JANE DOE”), the caption below it, then the numbered body, signature block, and jurat.
Writing the Facts So They Hold Up
Only put in what you personally saw, heard, or did. Federal evidence rules require a witness to have personal knowledge of what they testify about, and affidavits are held to the same standard.2Justia Law. Federal Rules of Evidence Rule 602 – Need for Personal Knowledge Courts routinely strike or ignore paragraphs that contain hearsay, speculation, or legal conclusions. If you did not witness it yourself, leave it out. A paragraph that begins “I was told that…” or “I believe that…” is the fastest way to weaken the rest of the document by association.
Be specific. “On March 14, 2026, at approximately 2:00 p.m., I saw the defendant’s vehicle run the red light at the intersection of Main and Oak” carries far more weight than “the defendant ran a red light.” Dates, times, addresses, and the names of anyone else present all make the statement harder to dismiss.
Where you are not certain, qualify honestly (“to the best of my recollection”) or cut the sentence. A careless exaggeration in a sworn document exposes you the same way a deliberate lie does.
Signing It: Notary or Declaration
There are two ways to execute an affidavit, and the one you should use depends on the court.
The traditional path is notarization. Bring the completed but unsigned affidavit and a valid government-issued photo ID to a notary. The notary checks the ID, administers a short oath (“Do you swear that the statements in this document are true to the best of your knowledge?”), watches you sign, and then completes the jurat with their signature, date, and seal. Do not sign beforehand; a notary who did not see you sign will refuse to notarize.
The second path, in federal matters and many state proceedings, skips the notary entirely. Under 28 U.S.C. ยง 1746, wherever federal law calls for a sworn affidavit, an unsworn written declaration works instead, so long as it includes the statement “I declare under penalty of perjury that the foregoing is true and correct” along with the date and your signature.3Office of the Law Revision Counsel. 28 USC 1746 – Unsworn Declarations Under Penalty of Perjury A declaration carries the same legal weight as a notarized affidavit and exposes you to the same perjury penalties. Many states, including California, have parallel statutes.
Before you spend time on a notary, check whether the court in your case accepts declarations. If it does, use the statutory closing language word for word. Getting it wrong can void the document. If the court requires traditional notarization, use that. Remote online notarization by video call is now permitted in most states, but not every court or every document type accepts a remotely notarized affidavit, so confirm before you rely on it.
Filing and Serving the Affidavit
Once the affidavit is executed, make at least two copies. File the original with the court clerk. Some courts require a paper original for notarized documents even when the rest of the case is filed electronically, and others take everything through the e-filing system. Ask before you show up.
You also have to serve a copy on every other party. Under the federal rules, that can be done by hand delivery, mail to the last known address, or electronic transmission where the recipient has consented or the court’s e-filing system handles it.4Legal Information Institute. Federal Rules of Civil Procedure Rule 5 – Serving and Filing Pleadings and Other Papers State rules track these methods closely. Watch the deadlines. An affidavit filed the day before a hearing when the rules required service five days out can be excluded.
Most courts also want a separate proof of service, sometimes called a certificate of service or affidavit of service. It is a short sworn statement giving the date, method, and address you used to deliver the document. Without it, the court may set your affidavit aside because there is nothing showing the other side received a copy.
What a False Statement Costs
Everything in an affidavit is sworn, and that includes a declaration under penalty of perjury. Anyone who willfully states something in either document that they do not believe to be true faces up to five years in federal prison, a fine, or both.1Office of the Law Revision Counsel. 18 USC 1621 – Perjury Generally State perjury statutes impose comparable penalties. Separate from prosecution, a court that catches a false affidavit can strike the document, sanction the filer with the other side’s attorney’s fees, or dismiss the underlying claim. Those consequences reach careless overstatements, not only outright lies. If you are not sure of a fact, qualify it or leave it out before you sign.