How to Prove Who Sent a Text Message
Reviewed by Jacob Reed, founder of Verity ·
Short answer
Usually with several small things that point the same way: you know the number is theirs, the messages mention things only they would know, they replied to what you wrote, they acted on it, and the carrier's records tie the number to their account. Under the federal rule, Rule 901, testimony from someone who knows, or the content and circumstances of the messages taken together, can be enough. A phone number on its own may not settle it, especially if they say someone else had the phone.
"That wasn't me" is a common answer to a damaging text. A record that answers it is built before the hearing.
What the rule asks for
Federal Rule of Evidence 901 asks for evidence "sufficient to support a finding" that an item is what it is claimed to be. Its examples include testimony of a witness with knowledge, and an item's appearance, contents, substance, internal patterns or other distinctive characteristics, taken together with all the circumstances. Family courts follow their own state's rules, many of them modeled on these.
What usually points to the sender
- The number: how you know it is theirs (they gave it to you, it is on school forms, you have called it).
- Content only they would know: the children's plans, a private nickname, something from that morning.
- Back-and-forth: replies that answer your questions, in a conversation that runs for months.
- What happened next: they turned up at the time the text set, or paid the amount it agreed.
- Their own words elsewhere: a later message, an email or a statement that refers to the text.
- The carrier's records, which can show the number belongs to their account and when messages were sent; see subpoenaing carrier records.
When they say someone else sent it
The answer is usually the same evidence: a long conversation in which the same person writes the same way about the same things is hard to put on someone else. Keep the whole thread, not only the damaging message, so the context is there (see the rule of completeness). New numbers after you blocked them raise the same question; see texts from new numbers.
What a numbered list does and doesn't show
Verity reads your export in your browser, without uploading it, and numbers every message in date order with the sender the export names, so the whole back-and-forth can be read in order. Its cover says plainly that it is not proof of authorship: a person with knowledge still has to say the conversation is what it appears to be. What it does is make the evidence above easy to point to by number.
The wider picture, including certified records, is in authenticating text messages.
Rule text cited
Read on November 3, 2026, from Cornell Law School's Legal Information Institute.
This is general information, not legal advice. Whether a message is admitted is for the court. Ask your attorney what your case needs.
Keep the whole conversation in order
Drop in your export and read every message numbered in date order. It is read in your browser and is not uploaded.