What is an autodialer (ATDS)?
13 min readRules read 2026-10-22
For the owner or ops lead whose team calls or texts customers: the TCPA's autodialer definition, what the Supreme Court did to it in 2021, how common dialers and texting platforms fare, and the three states that use a wider test. Every rule here was read in its own text on 2026-10-22.
The short answer
An autodialer, or ATDS, is the TCPA's name for equipment that can make up phone numbers with a random or sequential number generator and dial them. Since 2021 that is a narrow test, and most list-based dialers fall outside it. What it leaves behind is the part that still costs businesses money.
The legal definition, word for word
The phrase comes from the Telephone Consumer Protection Act of 1991. The definition is one sentence with two parts, and both have to be true of the equipment:
“The term “automatic telephone dialing system” means equipment which has the capacity—(A) to store or produce telephone numbers to be called, using a random or sequential number generator; and (B) to dial such numbers.”
The FCC's rule says the same thing and adds the short name everyone uses: “The terms automatic telephone dialing system and autodialer mean equipment which has the capacity to store or produce telephone numbers to be called using a random or sequential number generator and to dial such numbers” (47 CFR § 64.1200(f)(2)).
Why the label matters
The label decides which consent a call needs. Calling a cell phone “using any automatic telephone dialing system or an artificial or prerecorded voice” needs the called party's prior express consent unless it is an emergency (§ 227(b)(1)(A)(iii)). If the call is telemarketing, the FCC's rule raises that to prior express written consent (47 CFR § 64.1200(a)(2)), a signed agreement that prior express written consent takes apart line by line. Texts count as calls here, which is why the label matters as much to a texting platform as to a call centre.
Three words carry the weight. Capacity means what the equipment can do, not only what you used it for that day. Store or produce are the two ways a number can come out of the generator. Random or sequential number generator is the part that, until 2021, courts disagreed about: did it describe only how numbers are produced, or how they are stored too?
What Facebook v. Duguid decided
Noah Duguid got login-alert texts from Facebook for an account he never had, on a number he never gave Facebook (the Court notes it may have been a recycled number). He sued, arguing that any system that stores numbers and dials them automatically is an autodialer. The Supreme Court disagreed, unanimously:
“We hold that a necessary feature of an autodialer under §227(a)(1)(A) is the capacity to use a random or sequential number generator to either store or produce phone numbers to be called.”
Put simply, a system that only calls numbers somebody already has, a customer list, a CRM view, a file of leads, is not an autodialer under federal law just because it dials them automatically. The Court said Duguid's broader reading would classify “almost all modern cell phones as autodialers.” It also declined to make the test about how much a person is involved: “all devices require some human intervention,” and it would not draw “such a difficult line-drawing exercise around how much automation is too much” (footnote 6).
Footnote 7: the sentence vendors and plaintiffs both quote
Duguid argued that a device storing numbers with a generator would always produce them too, so the word “store” would add nothing. The Court answered with an example in footnote 7:
“For instance, an autodialer might use a random number generator to determine the order in which to pick phone numbers from a preproduced list. It would then store those numbers to be dialed at a later time.”
Plaintiffs read that as saying a dialer that shuffles a list can still be an autodialer. It is the Court's example of what “store” can mean, not a holding about list dialers, and the Ninth Circuit called the plaintiff's reading “an acontextual reading of a snippet” when it held, in Borden v. eFinancial (2022-11-16), that an autodialer must “generate and dial random or sequential telephone numbers.” That binds courts in one circuit; elsewhere the footnote is still argued.
What the ruling left covered
Duguid narrowed one definition. It did not touch the voice ban, and it has nothing to say about the rules that never depended on the dialer in the first place.
Prerecorded and artificial voices
A call to a cell phone using an artificial or prerecorded voice needs prior express consent (§ 227(b)(1)(A)), and so does a prerecorded call to a home line (§ 227(b)(1)(B)), with written consent for telemarketing (47 CFR § 64.1200(a)(2), (a)(3)). A voicemail drop is a recorded message. Ringless voicemail is too: the FCC ruled in 2022 that it “requires consumer consent because it is a ‘call’ made using an artificial or prerecorded voice” (FCC 22-85); the ringless voicemail comparison has the detail.
AI-generated voices
“In this Declaratory Ruling, we confirm that the TCPA’s restrictions on the use of “artificial or prerecorded voice” encompass current AI technologies that generate human voices.”
So an AI voice agent placing outbound calls needs prior express consent before it speaks, and prior express written consent if the call sells something (FCC 24-17 ¶ 5). Whether the platform behind it is an autodialer does not change that.
Everything that never depended on the label
The National Do Not Call Registry and your own do-not-call list, the 8 a.m. to 9 p.m. calling window, caller ID and the abandoned-call limit all apply to telemarketing calls whatever places them. The do-not-call rules for business cover the lists.
Predictive, power, preview, click-to-call and P2P texting
Vendors sell dialing modes, and the law asks about capacity. Here is how the FCC and the courts have treated each mode, and where nobody has settled it.
Predictive dialers
A predictive dialer calls several numbers per free agent and connects whoever answers. The FCC ruled in 2003 and 2008 that predictive dialers are autodialers, and its 2003 order said that held even for dialers that “cannot be programmed to generate random or sequential phone numbers,” as the D.C. Circuit recounted in ACA International v. FCC (2018-03-16). That court set aside the FCC's 2015 “explanation of which devices qualify as an ATDS,” and Duguid then made the generator a necessary feature. Whether the older rulings still count for anything is argued, and since 2025 a district court reads the statute for itself: it must “independently determine the law's meaning” while “affording appropriate respect to the agency's interpretation” (McLaughlin v. McKesson). The predictive dialer comparison covers the abandoned-call rule these dialers live under.
Power dialers
A power dialer calls one number per agent, in list order, as soon as the agent is free. It does not generate numbers, which is why vendors say theirs is not an autodialer. The open edge is footnote 7: a dialer that shuffles the list with a random number generator is closer to the Court's example than one that calls top to bottom. The power dialer comparison reads each vendor's claim.
Preview and click-to-call
In both, a person starts each call. The clearest federal line is the FCC staff ruling on peer-to-peer texting (below): a platform that cannot call “without a person actively and affirmatively manually dialing each one” is not an autodialer. Watch two things. A preview mode with a countdown that dials on its own is closer to a power dialer. And capacity counts, so a system that can switch to power mode sits beside the question rather than outside it.
Peer-to-peer texting platforms
In 2020 the FCC's Consumer and Governmental Affairs Bureau answered the P2P Alliance: sending to “a large volume of telephone numbers is not determinative,” and a texting platform that “lacks the capacity to transmit more than one message without a human manually dialing each recipient's number” is not an autodialer (DA 20-670). The Bureau did not rule on any particular platform, and the ruling came before Duguid. For a bulk platform sending a campaign to a list, the closest case is Borden, itself a texting case: no generator, no autodialer, in the Ninth Circuit. The TCPA rules for text messages cover what a texting program needs either way.
Is this setup an autodialer?
Each common setup, read three ways: the federal test after Duguid, and the wider state wording in Florida and in Oklahoma and Maryland, which reaches sales calls only. “Leans” means the text points one way and no ruling read for this page settles it; “Unsettled” means it could go either way.
This is about the equipment. Which mode a given record should go through, given its consent, is what the dialing-mode helper on the auto dialer comparison answers.
Show
| Setup | Federal TCPA after Duguid | Florida (sales calls) | Oklahoma and Maryland (sales calls) |
|---|---|---|---|
| Dialer that makes up random or sequential numbers | CoveredThe core of the Duguid holding: a generator produces the numbers it dials. | CoveredThe system both selects and dials. | CoveredAutomated selection and automated dialing. |
| Predictive dialer working an uploaded list | Leans outsideNo generator, so usually not since 2021. The FCC called predictive dialers autodialers in 2003 and 2008, so expect the argument. | Leans coveredThe software picks the next number and dials it, which reads close to selection and dialing. | Leans coveredOn the words, an automated system for dialing alone is enough. |
| Power dialer calling a list in the order you set | Leans outsideNo generator, which is the point vendors lean on when they say theirs is not an autodialer. | UnsettledThe dialing is automatic, but the order is yours. Florida asks for selection and dialing. | Leans coveredThe dialing is automated, and either function is enough on the words. |
| List dialer that shuffles the order with a random number generator | UnsettledFootnote 7 territory. Borden (9th Cir. 2022) held the generator must make phone numbers, not pick an order; that binds one circuit. | Leans coveredThe software selects the order and dials. | Leans coveredAutomated selection and automated dialing. |
| Preview dialer: the agent reads each record, then clicks to call | Leans outsideNo generator, and a person starts each call. A countdown that dials on its own is closer to a power dialer. | Leans outsideA person chooses each call. This is the cautious mode the dialer comparisons recommend for Florida leads. | UnsettledThe person selects, but the software still dials the digits. |
| Click-to-call from a CRM, one contact at a time | OutsideIf the system cannot call without a person starting each one, the FCC's 2020 ruling puts it outside. | Leans outsideA person selects and starts every call. | UnsettledThe click hands the dialing to software; no court reading of that was read for this page. |
| Desk or mobile phone dialled by hand | OutsideNo generator. Duguid declined to turn ordinary phones into autodialers. | OutsideNo automated system. | OutsideNo automated system. |
| Peer-to-peer texting: a person sends each text | Leans outsideThe FCC's 2020 ruling: outside only if it truly cannot send without a person dialling each number. | UnsettledFlorida counts a text as a sales call; a person selects, the platform sends. | UnsettledThe platform does the sending; no court reading of that was read for this page. |
| Texting platform sending a campaign to an opt-in list | Leans outsideNo generator. Borden itself was a texting case on a list of customers' numbers. | Leans coveredThe platform picks recipients by segment and sends to them. | Leans coveredAutomated selection and sending. |
| Prerecorded message, voicemail drop or ringless voicemail | CoveredA separate ban that does not depend on the dialer; Duguid left it untouched, and FCC 22-85 counts ringless voicemail as a call. | Covered"The playing of a recorded message" is named in the same clause. | CoveredBoth name the playing of a recorded message. |
| AI-generated voice agent | CoveredFCC 24-17: an AI voice is an artificial voice, so consent comes first whatever dials. | UnsettledThe clause says recorded message; an AI voice is not named. | UnsettledThe clauses say recorded message; Maryland's consent definition adds "artificial voice". |
47 U.S.C. § 227(a)(1)Fla. Stat. § 501.059(8)(a)15 O.S. § 775C.3(A)Md. Code, Com. Law § 14-4502(a)(3)
Read down the columns and a pattern shows. Federally, the line runs through the generator, so most rows lean outside except the two voice rows. In the three states it runs through automation, so the more the software chooses and dials, the more the state law reaches. For a sales call with no written consent, the setups that lean outside everywhere are the ones where a person picks and starts each call.
States that define it more broadly
Three states did not wait for the federal definition. Each bars sales calls made with an automated system unless the person signed written consent, and none of them asks about a number generator.
“A person may not make or knowingly allow to be made an unsolicited telephonic sales call if such call involves an automated system for the selection and dialing of telephone numbers or the playing of a recorded message when a connection is completed to a number called without the prior express written consent of the called party.”
Note the and. Florida's Telephone Solicitation Act said “selection or dialing” until a 2023 amendment (ch. 2023-150, approved 2023-05-25) changed it to “selection and dialing” and limited the clause to unsolicited sales calls. The same act made a text-message plaintiff reply STOP first and gave the sender 15 days to stop before a suit for damages (§ 501.059(10)(c)). Florida counts a text and a voicemail as a telephonic sales call, and a call to a Florida area code is presumed, until shown otherwise, to reach someone in Florida (§ 501.059(8)(d)).
Oklahoma and Maryland
Both still say or. Oklahoma bars a commercial telephonic sales call that “involves an automated system for the selection or dialing of telephone numbers or the playing of a recorded message” without prior express written consent (15 O.S. § 775C.3(A)). Maryland bars a telephone solicitation that involves “an automated system for the selection or dialing of telephone numbers” or a recorded message without it (Md. Code, Com. Law § 14-4502(a)(3)). On those words, automated dialing alone is enough. Both presume a call to one of their area codes reaches a resident (§ 775C.3(D); § 14-4503(b)).
What to do about it
Whether your dialer is an autodialer gets argued after a claim is filed. The records you keep before the call are what you can show on the day it arrives. In order:
The consent on record does more work than any dialer setting. A number whose owner signed written consent can be called by any mode the dialer offers, within the abandoned-call limit, and the label stops mattering. The Reassigned Numbers Database guide covers the one check that protects old consent, since a Facebook-style recycled number is exactly where consent fails.
This guide explains the rules; it is not legal advice.
Questions owners ask
What does ATDS stand for?
Automatic telephone dialing system, the TCPA's name for an autodialer. The statute defines it as equipment which has the capacity "(A) to store or produce telephone numbers to be called, using a random or sequential number generator; and (B) to dial such numbers" (47 U.S.C. § 227(a)(1)). The FCC's rule repeats it at 47 CFR § 64.1200(f)(2).
Is a predictive dialer an autodialer?
Usually not under federal law since Facebook v. Duguid, decided 2021-04-01, if it only calls a list you load and cannot generate numbers. The FCC said in 2003 and 2008 that predictive dialers qualify, so the label is still argued, and Florida, Oklahoma and Maryland ask a broader question for sales calls.
Does a vendor's "not an autodialer" claim protect me?
No. It is the vendor's reading of its own product, and the test turns on what the equipment has the capacity to do, which a court decides. It also says nothing about recorded or AI voices, the do-not-call rules, calling hours or state law, and you are the one who places the calls.
Is an AI voice agent an autodialer?
That is the wrong question to ask first. The FCC ruled in FCC 24-17 that the TCPA's restrictions on an artificial or prerecorded voice encompass current AI technologies that generate human voices. So the call needs prior express consent, and written consent for telemarketing, whatever dials it.
What did footnote 7 of Duguid say?
That "an autodialer might use a random number generator to determine the order in which to pick phone numbers from a preproduced list. It would then store those numbers to be dialed at a later time." It is the Court's example of what "store" can mean, not a holding. The Ninth Circuit read it narrowly in Borden v. eFinancial (2022).
What does an autodialer violation cost?
$500 per call or text, up to three times that ($1,500) if the court finds the violation willful or knowing. Each call or text is its own violation.
Sources
- 47 U.S.C. § 227, Restrictions on use of telephone equipment (govinfo, 2023 edition)fetched 2026-10-22
- 47 CFR § 64.1200, Delivery restrictions (eCFR, current as of 2026-10-20)fetched 2026-10-22
- Facebook, Inc. v. Duguid, No. 19-511 (U.S. Apr. 1, 2021), slip opinionfetched 2026-10-22
- ACA International v. FCC, No. 15-1211 (D.C. Cir. Mar. 16, 2018)fetched 2026-10-22
- Borden v. eFinancial, LLC, No. 21-35746 (9th Cir. Nov. 16, 2022)fetched 2026-10-22
- FCC Consumer and Governmental Affairs Bureau, P2P Alliance Declaratory Ruling, DA 20-670 (June 25, 2020)fetched 2026-10-22
- FCC 24-17, Declaratory Ruling on AI-generated voices (released Feb. 8, 2024)fetched 2026-10-22
- FCC 22-85, Declaratory Ruling and Order on ringless voicemail (released Nov. 21, 2022)fetched 2026-10-22
- McLaughlin Chiropractic Associates, Inc. v. McKesson Corp., No. 23-1226 (U.S. June 20, 2025), opinions pagefetched 2026-10-22
- Fla. Stat. § 501.059, Telephone solicitation (2026 Florida Statutes)fetched 2026-10-22
- Laws of Florida ch. 2023-150 (CS/CS/HB 761), approved May 25, 2023fetched 2026-10-22
- 15 O.S. § 775C.3, Oklahoma Telephone Solicitation Act (Title 15, complete text)fetched 2026-10-22
- Md. Code, Com. Law § 14-4502fetched 2026-10-22
- FCC, Reassigned Numbers Databasefetched 2026-10-22