CPaaS (Communications Platform as a Service) is a cloud-based, programmable multichannel communications platform that enables developers to customize and build on existing applications and software.

CPaaS offers turnkey communications capabilities such as voice calls, SMS messaging, video conferencing, and more that programmers can add to their software without the need for additional backend infrastructure or expensive hardware. In addition to communication, CPaaS provides additional app functionality like authentication/verification, call recording and transcription, caller identification tools, speech recognition, and more.

Here are some of the most common types of CPaaS applications and architecture:

What Is CPaaS

Unlike contact center software (CCaaS) or bundled Unified Communications services (UCaaS), CPaaS allows users to pick and choose which functions they’d like for their application to have.

In other words?

Users avoid paying for features they don’t need, and they get a high level of customizability and scalability.

The CPaaS market is slated to be valued at over $26 billion by 2026, with 70% of top-tier companies investing in API development.

Below, we’ll offer an in-depth definition of what CPaaS is and how it works, provide insight into its advantages and essential features, and introduce you to some of the top providers.


How CPaaS Works?



Though programmable communications APIs (Application Programming Interface) and SDKs (Software Development Kits.)

The API acts as a kind of “translator” between your existing application and another, external application that allows your app to gain functionality it didn’t previously have. Each API is a building block, containing a feature that your application needs to function at the highest level. Multiple APIs — building blocks — work together to add a new set of features to your existing app.

For example, if you wanted to add VoIP calling to your app, you’d need to find a Voice API.

APIs are a huge part of streamlined communications success — so much so, that over 85% of well-known, top-tier companies say that APIs are an effective strategy to grow their companies.

An SDK, on the other hand, is a suite of software development tools that makes it possible to create these applications in the first place. This means that SDKs often (if not always) contain APIs — but they also contain code and other rules developers must follow when integrating the SDKs that provide additional features and functionality.

Think of an API as the recipe for baking a cake from scratch, and an SDK as a store-bought cake mix that only requires the baker to add a couple of ingredients to make.


Top CPaaS Providers in 2021

Below, we’ll introduce you to three of the most well-known and popular CPaaS providers:

  • Avaya OneCloud
  • Twilio
  • Bandwidth

Each of these tools provides numerous communication channel APIs, identity verification functionality, and other standard features covered above. However, each tool is unique in the types of channels, specific features, pricing, and popular use cases.


Avaya OneCloud CPaaS


Avaya OneCloud


Avaya OneCloud is a CPaaS platform offering SMS and MMS messaging, local and toll-free VoIP voice calling and phone numbers, and carrier services to add to any application.

Available coding languages include Java, Python, PHP, .NET, Node.js, and Go — and users can contact Avaya directly if they’d prefer to work in another language.

Voice calling REST APIs makes it easy to integrate advanced calling features on the web, enterprise, or mobile applications. Users can embed AI into voice conversations thanks to partnerships with top providers like IBM Watson and Google Cloud. Automatic speech recognition, IP PBX and SIP integration, text-to-speech capabilities that can translate written text into over 20 languages, and audio conferencing functionalities are also available.

Additional Voice APIs include:

  • Interactive Voice Response (IVR) for improved customer self-service
  • Automatic and real-time communications transcription
  • Call analytics
  • CRM integration (Salesforce, etc.)
  • Voice effects (change pitch, speed, etc.)
  • Call recording
  • Caller ID masking for team members and customers
  • Click-to-call


SMS and MMS messaging functionalities make popular customer communication tactics like texting automation, message personalization, two-way texting, and bulk messaging with dedicated shortcodes possible. Users can even SMS-enable existing business phone numbers, get real-time SMS delivery status analytics, and send out automated text polls and surveys to customers.

Additional messaging capabilities include:

  • Free inbound messaging
  • Custom sender ID with a local phone number
  • Automatic long text splitting (after 160 characters)


Avaya’s Carrier Services are perhaps its strongest offering, as they allow for worldwide carrier lookup that provides key information about the caller or number like carrier, country code, and device type.

Users can also use Billing Name Address (BNA) and CNAM lookup to discover a number’s physical location, the caller’s name, and other identifying information.

This makes it easy for CPaaS users to segment and distribute leads by location. Increase campaign efficiency by learning the ideal time to schedule calls or messages, and offer a higher level of personalization.

Avaya also offers local phone numbers, shared or dedicated short codes, toll-free numbers, international numbers, and one-click integration with Google CCAI. Number porting for existing business phone numbers is also available.

Avaya’s pricing model lets users purchase communications credits on pay-as-you-go or auto-replenish models.

Basic pricing for communication channels is outlined in the table below.


Feature Pricing
Messaging Outbound Local SMS: $.005/text

Outbound Toll-Free SMS: $0.0085/message

Inbound Local SMS: Free

Inbound Toll-Free SMS: $0.0085/text

Voice Outbound Local Call: $0.015/minute

Outbound Toll-Free Call: $0.015/minute

Inbound Local Call: $0.02/minute

Inbound Toll-Free Call: $0.03/minute

Carrier Services Carrier Lookups: $0.01/lookup

BNA Lookups: $0.05/lookup

CNAM Lookup: $0.01/lookup

Local Phone Number Within The United States $1.00/number per month
Transcriptions Auto Transcription: $0.05/credit

Hybrid Transcription: $0.29/credit


Best For: Avaya is best for small to medium-sized companies that have more basic communications needs for their business applications, but that would benefit from access to advanced messaging and voice analytics to better understand their market. It’s also been especially popular as a tool for retailers to adjust to the COVID-19 pandemic, enabling things like Contact Tracing, Curbside Pickup, vaccination updates, and more.

For more information on Avaya, check out our Avaya overview.




Twilio CPaaS


Twilio is a highly customizable CPaaS solution offering not only communications APIs for channels like voice, SMS/MMS, video, WhatsApp, and Email, but also an advanced supernetwork connectivity infrastructure.

Twilio’s Programmable Voice API offers text-to-speech in 26 languages, speech recognition and transcription, answering machine detection, advanced call routing, and call recording.

Additional voice functionalities include:

  • Call queuing with intelligent hold
  • Audio conferencing for up to 250 participants
  • IVR and audio playback of pre-recorded voice prompts, music, etc.
  • Twilio SDKs to enable one-click calling in web interfaces or mobile applications
  • SIP integration
  • Voice insights and analytics


Toll-free, mobile, global, and local phone numbers are also available in over 100 countries.

Its text messaging APIs make it easy to send two-way SMS/MMS and WhatsApp messages, reminders, notifications, and even offer customer support via texting. Users can opt to redact the last four digits of phone numbers to protect customer and team member identity, manage opt-in and opt-out requests, send messages from short codes, send mass texts, automate messages, and check message delivery status.

The Twilio SendGrid Email API allows for sender authentication, email automation, email template creation, and provides valuable analytics and data regarding open rates and more. Users can also send marketing emails like product recommendations, customer loyalty program updates, and monthly newsletters that increase customer engagement and purchases.

Twilio also offers identity verification and anti-fraud APIs like its Lookup Tool, which is designed to improve overall message deliverability and increase lead conversions.

Twilio’s newest addition is its video communication API, which allows for both one-on-one video chats as well as larger rooms for up to 50 participants. Dial-in access, encrypted meeting recording, whiteboard, screen sharing, and live team chat messaging can also be used within video calls.

Users can not only look up caller ID names, carrier, and phone number information but can also access business “persona types” for improved market segmentation. Additional tools like Verify authenticate users via SMS, voice, email, or push notification codes, while the Authy API enables two-factor authentication.

Recently, Twilio added a Conversations API, which is an integrative messaging API uniting messaging conversations across SMS, chat messaging, WhatsApp, and MMS. This simplifies multi-channel messaging, improves access to message histories, offers native group texting, and lets team members scale conversations from 1:1 chats to conversations with 1,000 people, vastly improving the overall user experience.

Note that Twilio also offers Twilio Flex, which is a cloud communications solution that unifies omnichannel communication and is specifically designed for contact centers.

Below, we’ve outlined the pricing for some of Twilio’s top APIs. Note that Twilio offers pay-as-you-go pricing in addition to committed use and volume discounts, but that the below table illustrates pay-as-you-go pricing.


Feature Pricing
Programmable Voice Outbound Local Calls: From $0.013/minute

Inbound Local Calls: From $0.0085/minute

Toll-Free Inbound Calls: From $0.0130/minute

Toll-Free Outbound Calls: From $0.0220/minute

Programmable Messaging Outbound/Inbound Local SMS: $0.0075/text

Outbound Local MMS: $.0200/message

Inbound Local MMS: $0.0100/message

Inbound/Outbound Toll-Free SMS: $0.0075/text

Inbound/Outbound Short Codes SMS: $0.0075/text

Twilio SendGrid Email API 1 Free Plan for up to 100 emails/day

3 Paid Plans for over 100 emails/day from $14.95/month

Twilio Conversations Usage: $0.05/user per month

Media Storage: $0.25/GB per month

Programmable Video From $.004/participant per minute



Best For: Twilio is best for larger-scale corporations that need advanced communication APIs like email, WhatsApp, and video chat that aren’t always available with more basic CPaaS providers. Any business needing a highly customizable platform and multichannel communications with scalability will enjoy Twilio, but it’s especially popular within the Telehealth, Education, and eCommerce sectors.

For more information on Twilio, read our in-depth Twilio review of pricing and plans.




Bandwidth CPaaS


Bandwidth is a CPaaS provider that is unique in that it owns its own tier-1 carrier network (including telephone numbers.)

It offers authentication, video calling, in-browser WedRTC calling, voice, and messaging APIs — but unlike many other CpaaS solutions, it also offers an Emergency Calling API.

This means business apps and software can connect to emergency services — especially useful for companies with higher security needs and the potential for emergency situations (for example, if a rideshare app has a driver that gets into an accident.) Even better, the API also gives location information to the emergency service for faster arrival.

Bandwidth’s video API provides an in-browser video calling solution with screen sharing, call recording, and live video engagement tools.

The Bandwidth Messaging API allows for both standard and toll-free SMS messaging, group texting and group real-time notifications, and offers delivery receipts. Users can send over 1 million messages every day, including MMS texts with videos, audio, GIFS, and emojis. (Shortcodes are also available for bulk messaging.)

Voice API capabilities include:


  • Audio conferencing
  • Click-to-call
  • Call tracking
  • Number masking for enhanced security
  • IVR
  • Call transfers
  • Automated outbound voice reminders
  • Call recording
  • Text-to-speech
  • Call transcription
  • .WAV playback


Its authentication API enables multi-factor authentication with customizable messages and codes that expire after a set timeframe. Users will only pay for successful authentications, avoiding being charged for customer mistakes. The API also verifies phone numbers, uses voice authentication, and creates single-use passwords.

The WebRTC calling API lets users add a one-click voice calling capability to their web-based apps. It also stores call records, lets users send pre-recorded voice messages, enables call transfers, (warm and cold), and comes with call monitoring, call whisper, and call barge.

Its Caller ID management solutions let customers know who is calling them, while Phone Number Management allows for call automation, number porting, call tracking, and click-to-call. Users can choose up to 5,000 local numbers for their business phone system, creating private phone lines for application users, marketing phone lines, and more.

Though Bandwidth also offers volume and committed use discounts, the below pricing table outlines pay-as-you-go pricing models. Note that some pricing information is available only by directly contacting Bandwidth for a quote.



Feature Pricing
Voice API Domestic Inbound/Outbound Calls: $0.0055/minute

Call Transcription: $0.045/minute

Call Conferencing: $0.0015/minute

Text-to-Speech: $0.0007/100 characters

Call Recording: $0.002/minute

Messaging API Outbound SMS: $0.004/message

Toll-Free Outbound SMS: $0.0075/message

Shortcode Outbound: $0.006/message

Toll-Free Outbound MMS: $0.0185/message

Video API Consumed Stream: $0/0016/stream

Inbound Dial-In: $0.0055/dial-in

Authentication API $0.05/authentication


Best For: Bandwidth is best for businesses of all sizes that have a high volume of daily communication across multiple channels. It’s especially ideal for companies that want to enable communication from their web-based apps or software solutions. Because of its emergency services API, it’s a popular option for remote patient monitoring services, personal safety apps, and even home or commercial security providers.

For more information, read our Bandwidth review.

The CPaaS solution that’s best for your company depends heavily on the specific APIs and SDKs you need to improve your business application, streamline your overall workflow, and simplify essential business processes.

However, some key features to look for include:

  • Global Network Coverage, especially with private IP infrastructure for end-to-end encryption and increased reliability
  • Elastic SIP Trunking for scalability
  • Number porting
  • Local and toll-free phone numbers available for purchase
  • Wide variety of available communication APIs like voice and video calling, SMS messaging, social media messaging, chatbot integration, etc.
  • Verification and authentication APIs
  • Ability to integrate with preferred third-party apps/software
  • Pay-as-you-go pricing or volume discounts
  • Reporting and analytics
  • Supports multiple coding and programming languages
  • A diverse and robust developer community


The Pros and Cons of CPaaS

Below, we’ve outlined the most common pros and cons of CPaaS solutions based on user reviews and feedback from top CPaaS providers.


CPaaS Pros CPaaS Cons
Highly customizable, scalable a-la-carte communications channels and solutions for business apps  Requires a pre-built business application
Compatible with numerous coding languages like Python, Java, and more Creating successful custom applications requires at least some background knowledge of coding and development 
Improves the overall customer experience by adding higher levels of personalization, shorter customer wait times, and a faster overall customer resolution process Adding too many APIs to your application can sometimes impact its speed, causing lags/delays
Allows for omnichannel communication Potential security risks (DoS attacks, stolen credentials, data theft/hacking)



Essential CPaaS Features and Functionalities

CPaaS Features



Common CPaaS Use Cases

Given that CPaaS and APIs allow users to build almost anything, there is no limit to the ways in which businesses can use tools.

Below, we’ll discuss some of the most popular CPaaS use cases according to industry.



CPaaS has become even more popular in the healthcare field with the onset of the COVID-19 pandemic in 2020. Video APIs allow for telemedicine appointments without the need for a patient to come into a physical doctor’s office, and remote patient monitoring via the Internet of Things (IoT) makes it easy for medical professionals to keep an eye on levels and readings from medical devices from afar.

Patients can also use CPaaS features to book and manage appointments online or via a practice’s mobile app, sign up for appointment reminders, refill prescriptions, and even complete patient intake forms prior to appointments.

Medical professionals can then review these forms, send prescriptions to pharmacies, and access patient insurance information.



Within the financial industry, CPaaS can be used in customer interactions like automatic bank balance notifications, check deposits, one-on-one client video meetings, and sending out secure forms and documents.

Clients can also apply for loans and get real-time updates about the status of their loan applications.

Those using CPaaS within the finance industry should always check with regulatory agencies to ensure that they are following the proper compliance requirements when communicating with clients or sharing sensitive data via CPaaS solutions.



As you may have expected, CPaaS is the preferred business software of many brick-and-mortar and online retailers.

Shops can send out segmented special discount codes, sale alerts, in-store event registrations, and other offers based on a customer’s shopping industry. They can also let clients know when popular products have sold out or are about to be restocked.

Most importantly, CPaaS solutions let retailers provide detailed, real-time delivery updates and order confirmations. Shoppers can see when a shipping label was created, a package’s current location, select a preferred delivery time, and even see who signed for a package.


Hospitality Management and Travel

In addition to allowing people to view and book flights, tours, and hotel rooms with the click of a button, hospitality and travel industries use CPaaS to alert travelers to delayed/canceled flights, gate changes, available upgrades, and room changes.

Guests can easily place room service orders, book spa services, or directly message hotel management for any other needs. Hotels can also send check-out reminders, special discounts/offers, and provide a high level of personalized suggestions and service via SMS messaging.


Real Estate

Real estate agents can use CPaaS solutions — especially messaging APIs — to communicate with potential buyers/renters directly on their website or in their business mobile app.

Potential homeowners can book an in-person home tour, sign up for newsletters, or even take a private or public virtual tour where they have the opportunity to ask the real estate agent questions about the property in real-time.

Agents can send out appointment reminders, facilitate communication between buyer and seller, send forms and contracts for clients to complete, and securely provide property addresses to potential buyers.



CPaaS allows teachers to connect with parents and students without having to give out their personal phone numbers, email addresses, or other contact information.

Teachers can distribute handouts and homework, send forms and updates to parents/guardians, schedule parent-teacher conferences, or even text message students to provide quick clarifications when needed.

CPaaS can also be used to offer virtual campus tours, access course catalogs, and even update students and parents about weather-related school closings or other on-campus emergencies.

Additionally, the tool can be used to contact donors and alumni, making it easy to give back on a recurring schedule or with the click of a button.


Discover Additional CPaaS Providers

Now that you know more about the communications features and use cases of CPaaS — as well as the digital transformation it provides — you may want to learn more about the tools we’ve mentioned in this post and additional platforms.

Our interactive table of the best CPaaS providers offers overviews of essential and standout features, pricing information, and reviews from real users of solutions like Vonage, Sinch, Five9, MessageBird, and Kaleyra.



Below, we’ve answered some of the most common questions about CPaaS.


The cost of CPaaS platforms will depend on not only the specific APIs you select, but also if you opt for pay-as-you-go pricing, volume discounts, or a committed use discount. 

On average, you can expect to pay roughly between $360.00 to $480.00 per user each year, or about $35.00/user per month.  

First, ensure that the platform offers a wide variety of communications APIs. Remember to consider any functionalities and new communications channels you want to add in the future. This may include in-app social media chat channel integrations, omnichannel communication, authentication APIs, and management and reporting APIs.

Also study their network infrastructure, such as guaranteed uptime, data center location, coverage, and partner carrier networks. Research how the provider monitors their connections. 

Finally, take a hard look at their user and development community. 

Not only does a high-volume user community mean you’ll likely have the resources to solve issues or build APIs on your own, but it also provides invaluable insight into what you can build on on the platform. 

Believe it or not, it’s possible to manage CPaaS solutions and add APIs without advanced knowledge of coding and development. 

However, at least a baseline knowledge will speed up the process significantly. 

Granted, if you’re creating a business application, you either know yourself or have access to someone with a strong coding background. 

However, especially if you browse the user and development community of your CPaaS provider, you’ll be able to access step-by-step written and video tutorials on how to implement APIs, build applications, and more.