An affidavit authenticating documents is a sworn written statement in which a person with firsthand knowledge tells the court that an attached document is genuine and explains how they know. Get the structure and the sworn facts right and the document comes into evidence; get them wrong and the court can exclude the very record you need. What follows is what has to be in the affidavit, how to write the parts that courts actually scrutinize, and how to sign it so it holds up.
First, Check Whether You Even Need One
Federal Rule of Evidence 902 lists fourteen categories of “self-authenticating” evidence that courts accept without a supporting affidavit.1Legal Information Institute. Federal Rules of Evidence Rule 902 The ones that come up most often:
- Documents bearing the seal of a federal, state, or local government agency along with an authorized signature.
- Certified copies of public records, including court records and vital records certified by the official custodian.
- Official publications issued by a government authority.
- Newspapers and periodicals, offered to show what was published.
- Certified domestic business records that meet the business records exception, when accompanied by a written certification from the custodian.
- Certified electronic records generated by an electronic process or copied from a digital device.
If your document falls into one of these categories, submit it with the certification the rule calls for and skip the affidavit. For everything else, you need a sworn statement from someone who can personally vouch for the document.
What Has to Be in the Affidavit
Every authentication affidavit shares the same skeleton. Missing pieces give the opposing party an easy challenge.
Title and Caption
Label the document “Affidavit of Authenticity” or “Affidavit Authenticating Documents.” Below the title, state the venue where it is being signed, listing both the state and county. If the affidavit supports active litigation, add the full case caption: court name, parties, and case number.
Identification of the Affiant
Name the person swearing to the facts. Include their full legal name, current address, and their relationship to the document. That relationship is what establishes competence to testify: creator of the document, witness to its creation, or custodian of the records where it lives.
Personal Knowledge Paragraphs
This is the core of the affidavit. Federal Rule of Evidence 901 permits authentication through testimony from a witness with knowledge, meaning the affiant must speak from firsthand experience rather than repeating what someone else said.2Legal Information Institute. Federal Rules of Evidence Rule 901 Stick to observable facts and leave legal conclusions out. “I personally printed this bank statement from the institution’s online portal on March 15, 2026, and it is a true and accurate copy of the account record” works because it describes what the affiant did and saw. “This document is admissible under the business records exception” does not, because that is for the court to decide.
Exhibit
Attach the document itself as a labeled exhibit and reference it by label throughout the affidavit. Courts want the sworn statement and the document physically connected, not filed separately.
How to Draft the Personal Knowledge Section
Use numbered paragraphs, one fact per paragraph. A workable template:
- Paragraph 1: Full name, age over 18, and competence to make the affidavit.
- Paragraph 2: The affiant’s relationship to the document and the basis for personal knowledge.
- Paragraphs 3 through 5 as needed: Specific facts about the document’s creation, storage, or handling. When it was created, who created it, where it has been kept, and whether the copy being offered is identical to the original.
- Final paragraph: A statement that the document attached as an exhibit is a true and accurate copy, with the exhibit label identified (for example, “Exhibit A”).
Business Records
Business records are the most frequently authenticated type of document, and the hearsay rule exception that lets them in requires the affiant to cover specific ground. Rule 803(6) admits records of a regularly conducted activity only if the affidavit establishes each of the following elements.3Legal Information Institute. Federal Rules of Evidence Rule 803
- The record was made at or near the time of the event it describes, by someone with knowledge of that event.
- The record was kept as part of a regularly conducted business activity.
- Creating that type of record was a routine practice of the business, not something done specially for litigation.
- These conditions are shown through testimony of the custodian of records or another qualified person.
In practice the affiant is almost always the records custodian or a manager who oversees the recordkeeping system. The affidavit should describe the company’s standard recordkeeping procedures and confirm that the specific document was created and stored under those procedures. A workable statement: “As records custodian for XYZ Corporation, I maintain the company’s financial records in the ordinary course of business. Invoices are generated automatically by our billing system at the time each transaction occurs and stored in our electronic database. The attached Exhibit A is a true and accurate copy of Invoice No. 4521, retrieved from that database.”
The opposing party can still argue that the source of information or the method of preparation makes the record untrustworthy.3Legal Information Institute. Federal Rules of Evidence Rule 803 An affidavit that addresses each element directly makes that challenge much harder.
Electronic Records, Emails, and Screenshots
Emails, database exports, and files pulled from electronic storage can be self-authenticated under Rule 902(13) for records generated by an electronic system, or Rule 902(14) for data copied from an electronic device, when accompanied by a qualifying certification.1Legal Information Institute. Federal Rules of Evidence Rule 902 If you use an affidavit instead, speak to the reliability of the system that produced or stored the record. Identify the software or system, confirm it was functioning properly at the relevant time, and describe how the copy was retrieved and preserved.
For emails, state who sent the message, who received it, and confirm that the attached printout or file is an unaltered copy of the original communication. Screenshots need extra foundation because digital images are easy to alter: the affiant should identify the website or application captured, give the date and time of the capture, and confirm they personally took the screenshot.
Chain of Custody
For physical evidence and some digital files, the affidavit may need to establish an unbroken chain of custody, documenting every person who handled the item from collection through court. This matters most for items that could be tampered with or contaminated: drug test samples, forensic copies of hard drives, original signed contracts.
Cover these points:
- Who collected the item and when.
- How the item was stored and what security measures protected it.
- Every transfer of possession, with the name of each person who held the item, dates and times of transfer, and signatures.
- Confirmation that the item’s condition has not changed since collection.
If multiple people handled the item, each ideally signs a separate affidavit, or the primary affiant references a chain-of-custody log attached as an exhibit. Gaps give the opposing side grounds to argue the evidence was altered.
Signing: Notary or Declaration Under Penalty of Perjury
An affidavit is not effective until the affiant signs it under oath in the presence of a notary public or another official authorized to administer oaths. The notary completes the jurat, the block at the bottom certifying that the affiant appeared, was placed under oath, and signed on a specific date. The notary adds signature, official seal, and commission expiration date. Standard jurat language reads: “Subscribed and sworn to before me this [day] of [month], [year], by [affiant’s name].” Do not sign before you are in front of the notary; if the notary did not personally witness the signature, the jurat is defective and the affidavit can be thrown out.
In federal proceedings, you can often skip the notary entirely. Under 28 U.S.C. ยง 1746, anywhere federal law requires a sworn affidavit, you can substitute an unsworn written declaration signed under penalty of perjury, with the same legal weight. Replace the jurat with this line at the end: “I declare under penalty of perjury that the foregoing is true and correct. Executed on [date].” Then sign below it. Declarations executed outside the United States add the phrase “under the laws of the United States of America.”4Office of the Law Revision Counsel. 28 USC 1746 – Unsworn Declarations Under Penalty of Perjury
Declarations will not work for depositions, oaths of office, or oaths that must be taken before a specific official other than a notary. State courts vary on whether they accept declarations in place of notarized affidavits, so check your jurisdiction’s rules before skipping the notary in a state proceeding.
What False Statements Cost
Every statement in the affidavit is made under oath. A person who willfully states something material they do not believe to be true in a sworn affidavit commits perjury, punishable by up to five years in prison.5Office of the Law Revision Counsel. 18 USC 1621 – Perjury Generally The same penalty applies to false statements in unsworn declarations under penalty of perjury.
Beyond criminal exposure, Federal Rule of Civil Procedure 11 lets courts sanction attorneys and parties who submit affidavits containing false or frivolous representations, with sanctions ranging from orders to pay the opposing party’s attorney’s fees to penalties paid into the court or non-monetary directives aimed at preventing recurrence.6Legal Information Institute. Federal Rules of Civil Procedure Rule 11 – Signing Pleadings, Motions, and Other Papers; Representations to the Court; Sanctions The court can also strike the affidavit entirely, which excludes the document you were trying to authenticate along with it. If that document was central to your claims or defense, the case may be over.