To write an affidavit, put a title and your identifying information at the top, list the facts you personally know in numbered paragraphs, close with a statement swearing those facts are true, and sign the document in front of a notary public. For federal filings you can usually skip the notary by signing under penalty of perjury instead. The structure is the same whether the affidavit is going to a court, a bank, or a government agency; what changes is the facts you put in the middle and whether a notary needs to witness your signature.
The Four Parts Every Affidavit Needs
An affidavit is your sworn written testimony. Once signed and (where required) notarized, it carries the same legal weight as testimony given on a witness stand. The person signing is called the affiant, and every affidavit has four working parts.
The Heading
If the affidavit is tied to a court case, start with a caption listing the court name, case number, and the names of the parties. Below the caption, title the document “AFFIDAVIT OF [Your Full Legal Name].” If the affidavit is not tied to a pending case, say you are verifying your identity for a bank, you can skip the caption and lead with the title.
Under the title, add the state and county where you are signing. These two lines (called the venue) tell any reader where the oath was administered.
Your Identifying Information
Open the body with a sentence identifying yourself: your full legal name, your current address, and your connection to the matter. For example: “I, Jane Smith, reside at 123 Main Street, Springfield, and am the landlord of the property at 456 Oak Avenue.” This single sentence tells the reader who you are and why your testimony is relevant.
It is also standard to state that you are over eighteen, competent to make the affidavit, and have personal knowledge of the facts that follow.
The Numbered Facts
This is the core of the document, and it is where most mistakes get made. Each separate fact goes in its own numbered paragraph. Write in first person: “I observed,” “I signed,” “I received.” Lay the facts out chronologically; that order is easiest for both you and a judge to follow.
Every statement must come from your own personal knowledge. You can write “I saw the car run the red light” because you witnessed it. You cannot write “My neighbor told me the car ran the red light,” because that is hearsay. Federal Rule of Evidence 602 requires a witness to have personal knowledge of every matter they testify about, and courts can throw out affidavits, or the offending portions, when the affiant lacks firsthand knowledge.
Keep each paragraph focused on one point. If paragraph 3 covers a conversation on March 10 and paragraph 4 covers a letter received on March 15, that is two clean entries a judge can reference individually. Lumping them together makes the affidavit harder to work with and easier to challenge. If you witnessed part of an event but not all of it, say exactly what you saw and stop there.
The Closing Declaration
After the last numbered paragraph, add a sentence swearing the statements above are true. A standard closing reads: “I declare under penalty of perjury that the foregoing statements are true and correct to the best of my knowledge and belief.” Then date it and sign. If a notary is involved, you sign in the notary’s presence, not before.
A Sample Layout
The skeleton below shows how the four parts fit together. Replace the bracketed text with your own information.
AFFIDAVIT OF [YOUR FULL LEGAL NAME]
State of [State]
County of [County]
I, [Your Full Legal Name], being duly sworn, depose and state as follows:
1. I am over the age of eighteen and competent to make this affidavit. I have personal knowledge of the facts stated herein.
2. [First fact, stated in first person.]
3. [Second fact, stated in first person.]
4. [Continue numbering for each additional fact.]
I declare under penalty of perjury that the foregoing is true and correct.
Executed on [Date].
____________________________
[Your Printed Name]
[Your Signature]
[JURAT — completed by the notary]
Subscribed and sworn to before me this ____ day of __________, 20__.
____________________________
Notary Public
My commission expires: __________
[Notary Seal]
A court-filed affidavit adds a full caption above the title with the court name, case number, and parties. A standalone affidavit for a bank or government agency may omit the caption entirely.
Attaching Exhibits
If your affidavit references a document, a contract, a photograph, a receipt, attach it as an exhibit instead of trying to describe every detail in the text. Label each attachment sequentially (Exhibit A, Exhibit B, or Exhibit 1, Exhibit 2) and reference it in the relevant numbered paragraph: “Attached as Exhibit A is a true and correct copy of the lease agreement dated January 15, 2025.”
Place the exhibit label on the first page of each attachment so it is immediately identifiable. If you reference a foreign-language document, include both the original and a certified English translation. The translator should sign a certificate stating they are competent in both languages and that the translation is accurate.
Signing: Notary or Declaration Under Penalty of Perjury
How you finalize the affidavit depends on where it is going.
Under federal law, wherever a federal statute or regulation calls for a sworn affidavit, you can substitute an unsworn written declaration signed under penalty of perjury. The declaration carries the same legal weight as a notarized affidavit. To use this option, end the document with language tracking the statutory form, “I declare under penalty of perjury that the foregoing is true and correct. Executed on [date],” and sign. No notary, no seal, no jurat.
This substitute applies in federal proceedings and wherever federal rules govern, including immigration filings, federal court motions, and many agency submissions. It does not automatically work in state court. Most states have their own rules about unsworn declarations, and some require notarization for certain filings regardless. If your document is headed to a state court or state agency, confirm that jurisdiction’s requirements before skipping the notary.
When the affidavit does need notarization, three things happen in sequence at a single appointment. The notary verifies your identity by checking a government-issued photo ID such as a driver’s license or passport. The notary administers an oath or affirmation; you raise your right hand and swear, or affirm if you prefer a non-religious option, that the statements are true. You then sign the document while the notary watches, and the notary completes the jurat, signs it, and applies the official seal. Do not sign before you arrive at the notary. The point is that you sign in their presence after taking the oath.
Remote Online Notarization
You do not always need to visit a notary in person. As of early 2025, over 45 states and the District of Columbia have enacted permanent laws allowing remote online notarization, where you connect with the notary over a live video call. The notary verifies your identity through knowledge-based authentication questions and credential analysis of your ID, then watches you sign electronically during the session.
Remote notarization is useful if you are in a rural area, have mobility limitations, or need a document handled outside business hours. Fees for remote sessions run higher than in-person appointments, roughly $10 to $30 per notarial act depending on the state, sometimes with an added technology fee.
What Notarization Costs
Every state caps what a notary can charge per notarial act. For in-person notarization, the maximum ranges from as low as $2 in some states to $25 in others, with most falling in the $5 to $15 range. A few states set no maximum. Mobile notaries who travel to your location typically add a trip fee on top of the per-act charge. If cost is a concern, call ahead; many banks and credit unions notarize documents for account holders at no charge.
Penalties for False Statements
Filing a false affidavit is a crime. Federal perjury law makes it illegal to swear to any material statement you do not believe is true, whether in a traditional notarized affidavit or in an unsworn declaration under penalty of perjury. The penalty is a fine, imprisonment of up to five years, or both.
State perjury laws carry similar ranges, and the penalties can stack if you have violated both state and federal law. Beyond criminal prosecution, a court can impose civil sanctions on anyone who submits a false sworn statement, including striking the fraudulent document from the record, a reprimand, a monetary penalty payable to the court, and an order to pay the other side’s attorney’s fees and litigation expenses caused by the false filing.
The practical rule when drafting: do not include anything you are not sure about. Guessing, exaggerating, or repeating someone else’s account under oath is where people get into trouble.