The choice in front of you is not really a vendor choice. It is a single architectural decision, and every vendor you are comparing has already made it for you at a specific price point.

Does the system place one call at a time and hand it to a rep who is already sitting there, or does it place several calls at once and gamble that a rep will be free by the time somebody answers?

That is the whole of power dialer versus predictive dialer. A power dialer cannot abandon a call, because the rep is already connected before the phone rings. A predictive dialer can, because the rep is not, and that single fact is what drags a federal rulebook into the decision.

The seven modes, side by side

"Power" and "predictive" are two points on a spectrum that vendors label inconsistently. Here is the whole spectrum, because the mode you actually want is often one of the ones nobody is selling you.

Preview and progressive are worth knowing by name because they are what most people mean when they say "power dialer". In practice the terms collapse: preview gives the rep a beat to look at the record before committing, progressive removes that beat, and most products marketed as power dialers sit somewhere between the two. None of the three open a second line, so none of them can abandon a call.

Parallel dialing is the genuinely confusing one. It is sold under the power dialer name, most visibly by Kixie, but a second open line reintroduces exactly the abandonment risk the power dialer architecture removes. If a product dials more lines than it has reps, it is in predictive territory for regulatory purposes regardless of what the plan is called.

What the vendors you are comparing actually sell

All pricing below was checked against the vendors' own live pricing pages on 15 September 2026.

Close sells both modes in the same product and separates them by plan. Its help documentation describes a power dialer as technology that "dials a phone number right after a call is completed," and the predictive dialer as software that lets teams "dial multiple numbers simultaneously." The Power Dialer starts on the Growth plan at $99 per user per month billed annually ($109 per user per month billed monthly), and is included on Scale as well. The Predictive Dialer is exclusive to Scale, at $139 per user per month billed annually ($149 per user per month billed monthly). Note what that comparison does and does not tell you: Scale is a whole tier above Growth and carries other features besides parallel lines, so the $40 difference is the price of the tier, not a line item for the dialer.

Kixie splits the same way through plan names rather than features. Its Professional plan includes no power dialing. Above it sit a Single-Line PowerDialer plan and a Multi-Line PowerDialer plan that lets you "PowerDial up to 4 lines simultaneously," with AI Human Detection listed as a premium add-on rather than bundled. Kixie publishes no per-seat prices on its pricing page, which is worth knowing before you budget.

PhoneBurner is the honest outlier: a power dialer first, and not cheap. Standard is $140 per user per month billed annually ($165 monthly), Professional $165 annually ($195 monthly), Premium $183 annually ($215 monthly). All three tiers advertise unlimited calling, and the tiers differ mainly in how the rep connects. If raw single-line throughput for a dedicated calling floor is your only requirement, it is a legitimate choice.

GoHighLevel, which many agencies reading this already pay for, is where expectations go wrong. Its help documentation describes a Web Dialer, "a browser-based calling interface" with mute, hold, transfer, contact search, call scripts and automatic logging. That documentation does not describe predictive dialing, parallel calling, voicemail drop or answering machine detection. What HighLevel's own blog calls a power dialer is assembled from workflows: a "Manual Action to Call" step in an automation, a tag or pipeline change populating the list, and the rep working that list from the Conversations page. That is a call queue with a progress bar. Useful, but not the same category of machine as PhoneBurner or Close Scale.

Inflowave is a power dialer and only a power dialer. We place one call at a time from a queue built by filtering the CRM, and we do not offer predictive or parallel dialing. If you have decided you need four lines against a two hundred thousand record cold file, we are not the right tool and Kixie or Close Scale will serve you better.

Why parallel lines are attractive, without the fake arithmetic

The case for predictive is real. On a cold list most dials do not become conversations: they ring out, hit voicemail, reach a disconnected number, or get intercepted by somebody's assistant. A rep on a single line absorbs every one of those dead stretches personally. A predictive dialer places several calls, discards the dead ones before a human hears them, and connects the rep only to the live answers.

Resist the temptation to turn that into a neat multiplier. You will see the claim that a one-in-ten contact rate means a rep spends nine tenths of the hour listening to ringing. It does not follow: a dead dial ends at a voicemail greeting or a hang-up, a conversation can run for minutes, and how the hour divides depends on those durations rather than on the ratio of dials to answers. The honest version is directional. The lower your contact rate and the shorter your average conversation, the more parallel lines are worth. Measure your own ring-to-talk split for a week before you buy anything on this basis.

The cost is the part the sales page skips. The prediction is a bet on agent availability, and when the bet loses somebody has answered a call with no rep behind it. That is an abandoned call, and it is a legally defined term with a number attached.

The abandoned call rules, in the regulator's own words

Two federal rules govern this in the United States and they are close to identical, so you do not get to satisfy one and ignore the other.

The Federal Trade Commission's Telemarketing Sales Rule states that an outbound call "is 'abandoned' under this section if a person answers it and the telemarketer does not connect the call to a sales representative within two (2) seconds of the person's completed greeting" (16 CFR 310.4(b)(1)(iv)). The safe harbour that keeps a predictive dialer lawful requires that the seller or telemarketer "employs technology that ensures abandonment of no more than three (3) percent of all calls answered by a person, measured over the duration of a single calling campaign, if less than 30 days, or separately over each successive 30-day period." The same safe harbour requires that you let the phone "ring for at least fifteen (15) seconds or four (4) rings before disconnecting an unanswered call," that you play a recorded message naming the seller and its phone number whenever no rep is available within those two seconds, and that you retain records proving all of it.

The Federal Communications Commission's parallel rule under the TCPA says you may not "abandon more than three percent of all telemarketing calls that are answered live by a person, as measured over a 30-day period for a single calling campaign" (47 CFR 64.1200(a)(7)), using the same two-second definition.

Read those requirements as a build specification, because that is what they are. A compliant predictive dialer needs per-campaign rolling-30-day abandonment measurement, a fallback recorded identification message, a minimum ring duration it will not undercut, and an audit trail. If a vendor sells you parallel lines and cannot show you the abandonment rate per campaign for the last 30 days on a screen, you are carrying that risk, not them.

A single-line dialer sidesteps the apparatus entirely. One line, one rep, already connected, so the abandonment rate is structurally zero and the 3% cap, the two-second window and the fallback message never bind. That is not a marketing claim about our product. It is a property of the architecture, and it applies equally to PhoneBurner and to Close's Growth plan.

One related distinction gets muddled constantly. The TCPA's restrictions on "automatic telephone dialing systems" hang on a specific definition: 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)). A dialer working through known contacts your CRM already holds is a different thing from a machine generating numbers. That distinction matters, but it releases you from nothing else: consent requirements, do-not-call obligations and the rule prohibiting calls to a residence outside 8:00 a.m. to 9:00 p.m. local time at the called person's location (16 CFR 310.4(c)) all still apply. None of this is legal advice, and a compliance review with your own counsel is the right next step before any outbound programme goes live.

Answering machine detection is the dependency both modes share

Whichever mode you pick, the component doing the most work is answering machine detection, and it is imperfect in ways vendors rarely spell out.

Twilio's AMD documentation, the underlying detection layer for a large share of the market including ours, is unusually candid. In Enable mode it returns machine_start, human, fax or unknown as soon as it classifies the answer. In DetectMessageEnd mode it waits for the greeting to finish and returns machine_end_beep, machine_end_silence, machine_end_other, human, fax or unknown. It states plainly that detection "will not always return the right answer": a two-second voicemail greeting can read as a human, a long business greeting delays the machine classification, and a person who pauses mid-sentence can be classified as a machine. Tuning the parameters trades false-machine errors against false-human errors. You do not get both.

For a single-line dialer a misclassification costs one wasted moment. For a predictive dialer it is worse: a false-human classification pulls a rep off another conversation, and a false-machine classification hangs up on a real prospect. The error rate that is merely annoying on one line compounds on four.

Where we run detection, it is configured with the DetectMessageEnd value set, and coverage is thinner than that sentence on its own suggests: only 50 of 2,319 call log rows, 2.2%, carry any AMD classification at all. In that Inflowave production sample of 50 calls carrying an AMD classification, 9 March to 14 September 2026, the classifications recorded are machine_end_other, machine_end_beep, human and unknown, which tells you the feature is live rather than theoretical. It says nothing about how accurate the detection is, and we are not going to claim otherwise.

How the Inflowave power dialer runs, briefly

You do not upload a CSV. A dial session is built from a saved filter over your CRM records: pipeline stage, source, tag, last contact date, industry, or any custom field. Because the queue is a query rather than an import, a lead that converts or goes cold between sessions is simply not in the next one.

One item is live at a time and there is no concurrency setting to raise. A call log row opens immediately with direction, numbers, status, AMD classification and the identifiers tying the call to the lead, client, workspace and rep; duration, answer time, price, recording and any error code land on the same row afterwards. Each item closes with an outcome from a fixed vocabulary. In an Inflowave production sample of 995 dial session items, to 15 September 2026, the values recorded are connected, meeting_booked, not_interested, voicemail, no_answer, callback, wrong_number and abandoned. That last one needs naming rather than hiding, because it is not the regulator's abandoned call: it marks a queue item dropped before a call was ever placed, and 105 of the 107 items carrying it have no call identifier at all, meaning no phone ever rang and no person ever answered.

Because the call log, the lead, the opportunity and the messages are rows in one database rather than two systems joined by a nightly sync, a call sits beside the same person's DMs and emails in the unified inbox, stays searchable months later, and counts once in reporting. Scripts on screen, voicemail drops and per-client caller ID separation are covered on the power dialer feature page.

The limits, stated plainly

• No predictive or parallel dialing. One line. If you need four, buy Kixie or Close Scale.
• The scale is agency scale, not call-centre scale. This is not a product with a decade of call-floor deployments behind it. If you are staffing thirty seats against a purchased list, evaluate PhoneBurner honestly alongside us.
• A suppression list exists but is not yet carrying production volume. The do-not-call structure is in place and nobody has loaded one: both do-not-call tables are empty. Treat it as available rather than proven, and keep your own compliance process.
• Outcome-driven tag automation is built but effectively unused. The mapping from a call outcome to a CRM tag exists in the data model and has essentially never been exercised in production.
• AMD is probabilistic. See above. Nobody's is not.

How to choose, in four questions

1. Is your list cold and enormous? Low contact rates across hundreds of thousands of records are where the parallel-line multiplier earns its compliance apparatus. Go predictive, and insist on seeing per-campaign rolling abandonment reporting before you sign.
2. Are you calling inbound leads and existing contacts? Contact rates on fresh inbound are far higher, which shrinks the predictive advantage while keeping all of its downside. Power dial. See what cold calling actually involves for how the two list types diverge.
3. How many seats are actually dialing at once? A predictive algorithm needs a pool of agents to predict across. With a handful of reps on the phones there is almost no pool, the prediction has nothing to smooth over, and abandoned calls are how it tells you. The fewer concurrent dialers you have, the more a single-line mode is both safer and barely slower.
4. Do you want a rep on the line at all? If the first sixty seconds is the same qualification script every time, an AI voice agent places and qualifies the call without occupying a human, which changes the arithmetic more than any dialing mode does.

The honest summary: predictive dialing buys throughput and sells you a compliance programme. Power dialing buys simplicity and sells you fewer connects per hour. Small teams calling people who have already raised a hand should take the simplicity and spend the saved effort on what happens after the call connects.

Frequently asked questions

Are power dialers illegal?

No. A power dialer places one call at a time from a list of contacts you already hold, with a rep on the line, so it does not create abandoned calls. Legality depends on how you use it rather than on the tool: consent requirements, the national and internal do-not-call lists, and the rule prohibiting calls to a residence outside 8:00 a.m. to 9:00 p.m. local time at the called person's location all still apply. In other words, the dialing architecture is usually the easy part of compliance, and list sourcing, consent and timing are where enforcement actions tend to land. Check your own programme with counsel.

Are predictive dialers illegal?

Not inherently, but they operate inside a safe harbour with hard numbers. Under the FTC's Telemarketing Sales Rule and the FCC's TCPA rule you may abandon no more than three percent of calls answered live by a person, measured over each 30-day period per campaign. A call counts as abandoned if a rep is not connected within two seconds of the person's greeting. You must also ring for fifteen seconds or four rings, play a recorded message naming the seller when no rep is free, and keep records proving it.

What is the main difference between a predictive dialer and an auto dialer?

Auto dialer is the family name for any system that places calls without a person pressing digits. Predictive dialer is one member of that family, defined by dialing several numbers at once and predicting when an agent will be free. Power, preview and progressive dialers are other members, all single-line. So the difference is one of category: every predictive dialer is an auto dialer, but most auto dialers are not predictive.

What is the difference between preview, progressive and power dialing?

All three open one line at a time, so none of them can abandon a call. Preview dialing shows the rep the record and waits for them to commit, which suits complex sales where thirty seconds of research changes the conversation. Progressive dialing removes that pause and connects the next record automatically the moment the previous call ends. Power dialing is usually marketed as the progressive behaviour plus a screen pop, a script and automatic logging. Vendors use the three words loosely, so read the feature description rather than the label.

What are the key differences between a predictive dialer and a manual dialer?

Manual dialing means a person reads a number and enters it, one at a time, absorbing every ring, voicemail and disconnected line personally. A predictive dialer places multiple calls simultaneously, screens out the non-answers automatically, and connects the rep only to live humans. The trade is throughput against control: manual dialing produces no abandoned calls and lets a rep research each contact first, while predictive maximises talk time and requires a compliance programme.

What are the common problems with auto dialers?

Three recur. Answering machine detection misfires, since detection is probabilistic and a short greeting reads as a human while a long one delays the machine classification. Data quality degrades fast, because a dialer works through stale and wrong numbers just as happily as good ones. And logging tends to be the weak seam: if the dialer is a separate phone system that syncs to the CRM afterwards, outcomes and recordings drift away from the contact record they belong to.

What are the best dialers to use?

It depends on which mode you need. For parallel dialing, Close's Scale plan and Kixie's Multi-Line PowerDialer both sell it explicitly. For high-volume single-line dialing, PhoneBurner is the established specialist. If you already run HighLevel, understand that its dialer is a browser softphone with a workflow-driven call queue rather than a predictive system. If you want the dialer inside the CRM so calls, recordings and pipeline stages share one record, that is the case for Inflowave.

Is a power dialer free?

Rarely, and not at the vendors most people compare. As checked on 15 September 2026, Close puts its Power Dialer on the Growth plan at $99 per user per month billed annually, PhoneBurner starts at $140 per user per month billed annually, and Kixie charges for it as a separate plan tier above Professional without publishing a price. Watch how each vendor treats call minutes, because the models differ: PhoneBurner advertises unlimited calling within the seat price, while other products bill telephony usage on top of the seat, so a quote based on seat price alone can understate what you spend.

Sources

• Federal Trade Commission, Telemarketing Sales Rule, 16 CFR 310.4: https://www.ecfr.gov/current/title-16/chapter-I/subchapter-C/part-310/section-310.4
• Federal Communications Commission, 47 CFR 64.1200: https://www.ecfr.gov/current/title-47/chapter-I/subchapter-B/part-64/subpart-L/section-64.1200
• FTC, Complying with the Telemarketing Sales Rule: https://www.ftc.gov/business-guidance/resources/complying-telemarketing-sales-rule
• Twilio, Answering Machine Detection documentation: https://www.twilio.com/docs/voice/answering-machine-detection
• Close, Power and Predictive Dialing: https://help.close.com/docs/power-predictive-dialing
• Close pricing (checked 15 September 2026): https://www.close.com/pricing
• Kixie pricing (checked 15 September 2026): https://www.kixie.com/pricing/
• PhoneBurner pricing (checked 15 September 2026): https://www.phoneburner.com/pricing
• GoHighLevel, The Phone Dialer Overview: https://help.gohighlevel.com/support/solutions/articles/155000005807-the-phone-dialer-overview