Helpful Summary

• Overview: We compare four outbound dialers (power, parallel, predictive, and preview) to help you understand the key differences and use cases.

• Why Trust Us: We recently entered the outbound dialing space and have a unique perspective on which tools work best for different scenarios. 

• Why it Matters: Outbound dialers vary widely, and the wrong choice can tank your conversions.

• Action Points: Think about whether call quality or quantity is more important to you, and choose a dialer that aligns with that goal (or one like ServiceBell that caters to both).

• Further Research: Check out the ServiceBell blog for more tips on optimizing your outbound calling strategy.

Wondering About the Different Kinds of Outbound Dialers?

Outbound dialers have become a core part of (almost) every sales team’s toolbox. When used effectively, they can significantly increase call volumes and conversion rates. However, not all outbound dialers work or produce the same results.

In this ServiceBell guide, we demystify the four most common kinds of outbound dialers used by sales teams:

• Power dialers

• Parallel dialers

• Predictive dialers

• Preview dialers

We’ll explain what each kind of outbound dialer does when it makes sense to use each one, and the pros and cons of each. By the end of this guide, you’ll know which kind of dialer is right for you (and which ones you should probably avoid).

But first…

Why Listen To Us?

Harnessing the potential of outbound dialers correctly can significantly increase your pipeline.

At ServiceBell, we’ve watched customers like Sybill and DemandZEN grow their pipelines by $1 million and $500K, respectively, thanks to our suite of integrated inbound and outbound (i.e., allbound) sales tools.

The bottom line? Outbound dialing is a big part of our platform, so we know a thing or two about it.

What Is an Outbound Dialer?

An outbound dialer (also known as an autodialer) is a system that automatically dials phone numbers and connects you to the recipient. Rather than looking up a phone number, entering it manually, waiting for a connection, and manually hanging up, an outbound dialer handles all these tasks for you.

It’s an amazing tool for boosting call efficiency. But, as we mentioned in the intro, there are a few different kinds of outbound dialers—each with unique strengths and weaknesses.

4 Types of Outbound Dialers

1. Power dialers

2. Parallel dialers

3. Predictive dialers

4. Preview dialers

1. Power Dialers

A power dialer is the most “basic” kind of outbound dialer. Basic is in quotes because power dialers are anything but… they’re actually very powerful and flexible. However, the underlying technology is definitely the least sophisticated.

They automatically dial numbers in sequence (i.e., one after the other). When the dialer connects with a live person, the rep using the power dialer is able to dive right into the conversation with no lag time.

Advanced power dialers like ServiceBell also offer features like voicemail drop for faster and more efficient dialing, as well as CRM integrations for syncing notes and prospect/account information between the dialer and the CRM.

Benefits of Power Dialers

• Good Personalization: Since numbers are dialed one at a time, your reps have time to pull up information about the lead before the call connects. With tools like ServiceBell, this is even automated. The result? More personalized, effective calls.

• Solid Efficiency: Power dialers offer a good balance between personalization and volume. We covered personalization above, but it’s important to remember that your reps are also saving tons of time by not manually dialing each number.

Drawbacks of Power Dialers

• Not the Most Efficient: Even though power dialers are more efficient than manual dialing, they aren’t even close to your most efficient option.

When to Use Power Dialers

Power dialers work best in situations where you have a small to medium list of high-value numbers you need to call quickly. For example, if you have a list of especially hot leads or VIP clients that you need to connect with as soon as possible, a power dialer will be perfect.

2. Parallel Dialers

A parallel dialer is a very different beast. This kind of dialer dials numbers in parallel (i.e., multiple calls at once) and connects the first person to pick up the phone. Since the rep isn’t actually on the line with every pending call, the system needs to automate the transfer.

The number of lines you can dial in parallel depends on the type of dialer you’re using and your phone system’s capabilities. For example, ServiceBell’s parallel dialer can dial 2-9 numbers at a time, depending on your needs.

Another essential feature of parallel dialers is AMD—or answering machine detection. This stops your reps from getting connected to voicemails. ServiceBell’s AMD actually uses AI to make this process extremely quick and reliable.

Benefits of Parallel Dialers

• Higher Call Volumes: The main benefit of power dialers is higher call volumes. A team of 10 using a 10-line parallel dialer could theoretically work through a call list of 1,000 phone numbers in just over an hour.

• More Efficiency: On a related note, parallel dialers mean that you’re maximizing the amount of time your reps spend talking to leads. Waiting for successful connections is often the biggest drain on time, and parallel dialers keep this to a minimum.

Drawbacks of Parallel Dialers

• Less Personal: One of the biggest drawbacks of power dialers is that they can feel impersonal to prospects. With multiple calls being made at once, you don’t know who you’ll be connected with—and that means you can’t prepare as effectively.

• Potentially Annoying: With certain parallel dialers, there’s a chance that numbers that don’t connect get recycled back into the call list for future attempts. This means repeat rings and (potentially) annoyed customers.

When to Use Parallel Dialers

Parallel dialers are all about high-call volumes. As a result, they work best in situations where:

• You’re not too worried about personalization (e.g., cold calling)

• You have a large contact list (e.g., qualifying a huge number of leads)

• You need to reach a high number of prospects in a short amount of time (e.g., call blitzes)

• You want to increase productivity (e.g., lean startups)

3. Predictive Dialers

Predictive dialers are like power dialers on steroids. They use algorithms to predict when a sales rep will become available and automatically dial numbers so that as one call ends, another begins. This helps maximize the time reps spend talking to prospects.

With this kind of outbound dialer, the algorithm is everything. If able to give you accurate predictions, great—you’ll definitely see an increase in performance. But if the algorithm is off, it can lead to major issues. 

Think about it—if you answered a call and heard nothing but silence for 5 seconds, would you stick around? Small algorithmic errors like that can really hurt performance.

Benefits of Predictive Dialers

• Potential Time Savings: If your algorithm is finely tuned, a predictive dialer can theoretically lead to more time on calls than a power dialer. However, a parallel dialer still offers the most out of all the options so far.

• Good Personalization: As soon as a new number starts dialing, a predictive dialing tool can pull up prospect information from a database. This lets agents prepare for the call ahead while they finish up the previous call.

Drawbacks of Predictive Dialers

• Reliance on Algorithms: Predictive dialers are very reliant on their underlying algorithms. As a result, errors are more likely to occur and can significantly impact performance. With less technical tools like power and parallel dialers, this isn’t an issue (which is a big reason why we’ve prioritized these tools for ServiceBell).

When to Use Predictive Dialers

We recommend limiting predictive dialer usage to situations where you’re contacting low-urgency, low-value leads. That way, you don’t need to worry too much if you lose a few opportunities due to lag time and connection issues.

4. Preview Dialers

Last up, we have preview dialers.

This is a less well-known kind of outbound dialer that (as the name suggests) lets reps preview information about a prospect or lead before placing the call. They usually integrate very tightly with CRMs so that information can be easily accessed and updated.

Out of all the tools on this list, preview dialers involve the most manual effort—but there’s a good reason for it. These tools are designed for scenarios where reps need to know key details about the person they’re connecting with before the call.

Benefits of Preview Dialers

• Great Personalization: Preview dialers are great for high-quality, personalized calls—it’s their entire purpose. Reps have as much time as they need to review information and tailor their pitch accordingly.

• Improved Customer Experience: Knowing about a prospect or lead before making the call allows reps to have more meaningful conversations and provide a better customer experience. This can lead to higher conversion rates and happier customers.

Drawbacks of Preview Dialers

• Less Efficient: As you’ve probably gathered, these aren’t the fastest outbound dialers. That isn’t always a drawback, but in many cases, it limits the number of calls reps can make in a day.

When to Use Preview Dialers

You should look into preview dialers if you’re dealing with highly technical industries. For example, if you need to be able to sell your solution to a very specific use case, a preview dialer could help you do just that.

So… Which Outbound Dialer Should You Choose?

This is a tough question to answer without knowing your exact situation. However, the easiest way to think about the question is this—do you prioritize call quality or quantity?

For small sales teams that need to maintain a high level of quality, a power dialer or preview dialer will be the best fit. For sales teams that deal with huge call lists, a parallel dialer or predictive dialer will be the best option for getting through it quickly.

However, it’s always helpful to have a bit of flexibility. ServiceBell caters to this need by letting you toggle between power and parallel dialing modes.

Running a high-volume call blitz? Switch into parallel dialing mode and watch as your team flies through the list. Working with a list of high-intent ICPs pulled from your pricing page? Our power dialer and CRM integrations will help you impress.

Plus, both of our dialing modes are “inbound-aware.” This means they’re fully integrated into our allbound (outbound + inbound) sales platform. For example, you can use ServiceBell to create complex, high-performing workflows like this:

1. Get alerts when there are visitors on high-intent pages.

2. Identify these visitors using your ICP criteria.

3. Enrich their profiles with our third-party integrations.

4. Add them directly to your call list for highly targeted outreach.

5. Schedule meetings without leaving the platform.

Power vs. Parallel vs. Predictive vs. Preview Dialers: Comparison Table

Conclusion

Outbound dialers can be a huge benefit for your sales team. But you need to choose the right one for your needs.

Looking for an outbound dialer that can do it all (and then some)?

ServiceBell Outbound lets you access a fully featured outbound dialer that can toggle between power and parallel dialing modes as needed. Plus, it’s fully integrated with our other sales tools—including live chat, visitor identification, alerts, routing, and more.

Schedule a demo to see the difference firsthand.

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