Junk Fax Law: Your Rights Under the Junk Fax Prevention Act

The junk fax rule

The TCPA has banned junk faxes since 1991. The Junk Fax Prevention Act of 2005 rewrote the rule into its current form. Today, 47 U.S.C. 227(b)(1)(C) makes it unlawful “to use any telephone facsimile machine, computer, or other device to send, to a telephone facsimile machine, an unsolicited advertisement,” unless all three of these are true:

1. The sender has an established business relationship with the recipient.
2. The sender got the fax number either from the recipient within that relationship, or from a directory, ad or website where the recipient agreed to publish it.
3. The fax carries an opt-out notice that meets the statute and the FCC’s rule.

The FCC’s version is 47 CFR 64.1200(a)(4). The ban protects business fax lines as well as home ones, and the right to sue in 227(b)(3) belongs to any “person or entity.”

What counts as an “unsolicited advertisement”

The statute defines it as “any material advertising the commercial availability or quality of any property, goods, or services which is transmitted to any person without that person’s prior express invitation or permission, in writing or otherwise” (227(a)(5)). A flyer for a seminar with a paid product at the end, a price list, or a “free” offer that leads to a sale can qualify. Your permission can be given “in writing or otherwise,” so a phone call asking for a price sheet counts as permission for that fax.

The business relationship exception for faxes

For faxes, an established business relationship is “a prior or existing relationship formed by a voluntary two-way communication” based on “an inquiry, application, purchase or transaction” by the recipient (64.1200(f)(6)). Unlike the telemarketing version, the fax definition has no 18-month or 3-month time limit, and it covers business subscribers.

The relationship alone is not enough. The sender must also have obtained your fax number from you within that relationship, or from a directory, ad or website where you voluntarily made it public. If a sender pulls a number from your own website or ad, the rule presumes you made it available, unless the material says you do not accept unsolicited ads at that number (64.1200(a)(4)(ii)(B)). A narrow grandfather clause covers relationships and numbers a sender had before July 9, 2005.

Your opt-out ends the relationship exception for future fax ads (64.1200(a)(4)(v)).

What the opt-out notice must say

Even a fax sent under the business relationship exception is unlawful without a compliant notice. Under 227(b)(2)(D) and 64.1200(a)(4)(iii), the notice must:

• be “clear and conspicuous and on the first page of the advertisement,” placed at the top or bottom of the fax (64.1200(f)(3));
• say you can ask the sender not to send future fax ads, and that failure to comply within 30 days is unlawful;
• explain what a valid opt-out request must include;
• give a domestic telephone number and fax number for opt-out requests;
• give a cost-free way to opt out, such as a website or email, if neither number is toll-free; and
• let you opt out “24 hours a day, 7 days a week.”

A tiny line at the bottom that says only “to be removed, call” with a number does not meet all of these. A missing or defective notice is often the key issue in a fax case, because it can defeat the business relationship defense.

Opting out and the 30-day deadline

A valid opt-out request identifies the fax number or numbers it covers and goes to the phone number, fax number, website or email given in the notice (64.1200(a)(4)(iv)). The sender “must honor that request within the shortest reasonable time from the date of such request, not to exceed 30 days” (64.1200(a)(4)(v)). If a third party manages the sender’s list, the sender is still liable for failures. After that, only your new “prior express invitation or permission” allows more fax ads.

Other fax requirements

• Header identification. Any fax sent by computer must show, in a margin at the top or bottom of each page or on the first page, the date and time sent, the sender’s identity, and the sending phone number (227(d)(1)(B)).
• Fax broadcasters. A company paid to blast faxes for others is liable if it had “a high degree of involvement in, or actual notice of, the unlawful activity” and did not stop it (64.1200(a)(4)(vi)).
• No fax-line probing. Callers may not dial numbers to find out whether a line is a fax or voice line (64.1200(a)(8)).
• Not on the Do Not Call Registry. The FTC notes that fax lines are not covered by the Registry. The fax rules above are what protect you.

Online fax services after McLaughlin v. McKesson (2025)

Many businesses now receive faxes as emails or PDFs through online fax services. The FCC ruled, in its Amerifactors order, that an online fax service is not a “telephone facsimile machine,” which would put those faxes outside the TCPA.

That ruling was at the center of McLaughlin Chiropractic Associates v. McKesson Corp.. McKesson sent unsolicited fax ads to medical practices in 2009 and 2010. The district court treated Amerifactors as binding, threw out the claims of recipients who used online fax services, decertified the class, and cut McLaughlin’s own recovery to $6,000 for 12 traditional faxes.

On June 20, 2025, the Supreme Court reversed that approach, 6 to 3. The Court held that the Hobbs Act “does not preclude district courts in enforcement proceedings from independently assessing whether an agency’s interpretation of the relevant statute is correct.” Courts are not bound by FCC interpretations like Amerifactors, though they give the agency’s view appropriate weight. Whether an online fax service is a “telephone facsimile machine” is now a question each court decides by reading the statute. The statute’s definition covers equipment with “the capacity” to transcribe text or images “from an electronic signal received over a regular telephone line onto paper” (227(a)(3)). Expect litigation over what that means for e-fax inboxes.

Damages for junk faxes

Junk fax claims fall under 227(b)(3): actual loss or $500 per fax, whichever is greater, and up to $1,500 per fax if the sender acted willfully or knowingly. Twenty unlawful faxes comes to $10,000 at the base rate. Fax campaigns can go to thousands of numbers at once, one reason fax cases are often brought as class actions; see our TCPA class action guide. The penalties page has worked examples, and the four-year deadline for each fax is explained on our statute of limitations page.

Who can be sued for a junk fax

The FCC’s rules put liability on the “sender,” defined as “the person or entity on whose behalf a facsimile unsolicited advertisement is sent or whose goods or services are advertised or promoted in the unsolicited advertisement” (64.1200(f)(11)). The business being advertised can be the defendant even if a marketing firm pressed send. A fax broadcaster can share liability when it was closely involved or had notice and did nothing, as described above.

How to preserve junk fax evidence

• Keep the original fax, paper or PDF. Do not write on it.
• Note the date received and the number of pages.
• Keep the fax header line, which shows the sending number and time.
• If you send an opt-out, keep a copy and the confirmation page.
• Keep a record of whether you ever did business with the sender, and whether your fax number is published anywhere with a “no unsolicited ads” note.

Track each fax the same way you would a call in our evidence log.

If your office keeps getting fax ads

Gather the faxes from the last four years in one folder. Check each first page for the opt-out notice elements listed above. Send one opt-out request to the number in the notice and date it. If ads keep arriving more than 30 days later, or if the notices were missing or incomplete, you may have a claim for each fax. Our guide on suing a telemarketer covers the process, which works the same way for fax senders.