Award-Winning VoIP
Business Phone Solutions

We've made it easy to communicate since 1987!

Premier Provider of Cloud & On-Premises Telecommunications that bring together
Desktop Phones, Smartphone & Softphone Apps, Texting, Video Conferencing, A.I. Collaboration and so much more!

Cloud (Hosted) VoIP

eCloud PBX™

Ideal for the modern distributed workforce, the Cloud delivers cutting-edge performance and reliability, while empowering employee efficiency and productivity - across one locale or several around the country.

On-Premises

eSIP Evolution Series™

To keep pace with competitors today's on-site solutions need the power to outperform, the flexibility to handle many tasks, and the intelligent feature sets to help fuel effective employee conversations with your valuable customers.

On-Premises + SIP Trunks

eSIP-as-a-Service™

Level-up your on-site communications with a 'winning combination' of the ESI eSIP Evolution Series™, ESI ePhones™, and ESI SIP Trunks to unlock powerful Cloud functionality with extended features and benefits.

Why Are Businesses Nationwide Choosing ESI?

We're all about making business communication easy. Whether you need cloud or on-premises phone systems, we've got you covered with high-performance solutions that are not only easy to use but also uniquely integrated.

Our Proven Experience: Founded in 1987, we know a thing or two about keeping calls connected and conversations flowing. We also have the hardware to back it up, with numerous patents and industry awards.

Powerful Tools & Leading Technology: Enterprise-level features to promote employee productivity and efficiency, blended with a communications suite from voice to video.

Simple & Intuitive: Our solutions are designed and developed to be intuitive and user friendly, making managing one or one-hundred users easy and stress-free.

Don't take our word for it...

Read what some of our customers say:

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Switching to the ESI cloud phone system has been a game-changer... We've significantly reduced our phone bills... Managing and administering the phone system... has become much easier, allowing us to focus more on serving our community. The transition has been smooth and incredibly beneficial for our operations.

"Michael" H.

Community Non-Profit

★★★★★

ESI knows what they are doing... They made it easy for us to understand the basic in's/out's of VOIP phones. If I had a question on how to do something, one call to ESI and a tech would remote into my PC and show me. Speaking of support, I have always talked to someone here in the US and response time is practically nil.

"Ronald" B.

School District

★★★★★

"We have used ESI for 6 years. We have been very happy with their service! The phones are great and we never have any issue replacing parts or phones when needed. Their support team is always available and quick to help. We highly recommend them!"

Stacy W.

Medical Office

★★★★★

We've had ESI service for several years and it's been great. It's been reliable and stable. We rely on our phone system and internet fax for our business and it's been wonderful having a system that works when we need it. The phone equipment has been easy to use and program too. We love it!

David K.

Retail Office

★★★★★

ESI impresses with their top-notch phone services. From crystal-clear call quality to seamless integration of advanced features, they've mastered communication solutions.

Anthony H.

Charitable Non-Profit

★★★★★

[We have] been thrilled with our... purchase. This reasonably priced system harnesses cutting-edge technology, ensuring our office staff remains easily accessible and connected at all times.

Lee W.

Lumber Company

★★★★★

Many small office phone systems expect you to memorize a host of key strokes... [ESI] is far simpler to use and the phones themselves have been rock solid in terms of performance since installation.

Marc M.

Power Supply Reseller

★★★★★

The whole process was very easy for the purchase, installation, and training of a VoIP Phone system solution. The cost was very competitive and post-sale Tech Support has been good.

Tim N.

Printing Equipment Reseller

★★★★★

Our experience with ESI has been a great one. They helped us upgrade our phone system. Anytime that I have needed assistance, they have helped me with quick turnaround time. I highly recommend them.

Gloria S.

Credit Union

★★★★★

Our company has used ESI's VoIP services for a few years now and we have never had any issues with service or customer service... We feel confident referring other companies to use their service.

Brittany B.

Legal Organization

★★★★★

All my experiences with ESI have been more than positive. [ESI] goes above and beyond for anything I need. I appreciate your service.

Kathi H.

Family Services

★★★★★

Excellent VOIP platform. Would recommend using them for their equipment and service.

Ken G.

Financial Services

★★★★★

Check out a few of our Case Studies from actual ESI customers:

ESI Case Study: Automotive

The ESI eCloud PBX™ drives reliable and consistent customer communications for a family-owned dealer of iconic brand in the Northeastern U.S.

ESI Case Study: Property Management

ESI’s Cloud and On-premises solutions help a major property management company headquartered in Dallas, TX better serve their customers.

ESI Case Study: Retailer/Franchise

The ESI eCloud PBX™ helps a major auto parts retail store recover from a massive twelve day outage in record time.

ESI Case Study: Religious Organization

US Patent 6,067,349 for ‘Dialing Using Caller ID’
US Patent 6,252,944 B1 for ‘Telephone Call/Voice Processing System’
US Patent 6,842,505 B1 for ‘Communications System Enhanced with Human Presence Sensing Capabilities’
US Patent 6,940,962 B1 for ‘Dial On-Hold’
US Patent 6,925,167 B2 for ‘Service Observing in a Voice Over IP Telephone System’
US Patent 7,068,684 B1 for ‘Quality of Service in a Voice Over IP Telephone System’
US Patent 7,123,699 B2 for ‘Voice Mail in a Voice Over IP Telephone System’
US Patent 7,221,741 B1 for ‘Dialing Using Caller ID’
US Patent 7,466,696 for 'Application or service communication using multiple communication mediums'
US Patent 7,564,834 for ‘Shared Knowledge in a Voice Over IP Telephone System’
US Patent 7,916,651 for 'Application or service communication using multiple communication mediums'
US Patent 8,249,590 for 'Voice call handoff between communication mediums, such as cellular and Wi-Fi'
US Patent 8,391,298 B2 for ‘Phone Directory in a Voice Over IP Telephone System’

Industry Awards

2025 - Product of the Year*
(ESI ePhone 8™)
2025 - Product of the Year*
(ESI ePhone 4x™)
2025 - Product of the Year*
(ESI ePhone 3™)
2024 - Product of the Year*
(ESI eCloud PBX™)
2024 - UC Product of the Year*
(ESI eCloud PBX™)
2023 - Hosted VoIP Excellence*
(ESI eCloud PBX™)
2023 - Teleworking Excellence*
(ESI eCloud PBX™)
2021 - Product of the Year*
(ESI eCloud PBX™)
2021 - Product of the Year*
(ESI ePhone 8™)
2020 - Product of the Year*
(ESI eSIP Titan Series™)
2020 - Product of the Year*
(ESI ePhone 4x™)
2020 - Product of the Year*
(ESI ePhone 3™)
2019 - Product of the Year*
(ESI eSIP Evolution Series™)

2017 - Product of the Year*
(ESI ePhone7™)
2017 - Friend of the Channel*
(ESI Partner Program)
2016 - Top 10 Unified Communications Solutions Providers (ESI) by Enterprise Networking
2016 - The 30 Most Valuable Tech Titans (ESI) by Insights Success magazine
2015 - Product of the Year*
(ESI eCloud PBX™)
2015 - UC Product of the Year*
(ESI eCloud PBX™)
2014 - Channel Excellence*
(ESI Partner Program)
2004 - Product of the Year*
(VIP, Visually Integrated Phone™)
2003 - Product of the Year*
(ESI E-Class™ systems)
2002 - Product of the Year*
(ESI EsiLink™)
2001 - Product of the Year*
(ESI Remote IP Feature Phone™)
2001 - Product of the Year*
(ESI IP 200™)

Systems

Cloud Phones for Lawyers delivers a single platform for all your voice and text communications.

Devices

ESI’s award-winning equipment is designed to take advantage of today’s cloud-based voice technology.

Applications

ESI integrates with Outlook, Google and leading Practice Management Systems, including Clio.

Integrations

ESI is a proven leader, providing end-to-end law firm communications systems for more than three decades.

Access

Client Testimonials

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Award-Winning VoIP Business Phone Solutions

We've made it easy to communicate since 1987!

Cloud (Hosted) VoIP

eCloud PBX™

On-Premises

eSIP Evolution Series™

On-Premises + SIP Trunks

eSIP-as-a-Service™

Why Are Businesses Nationwide Choosing ESI?

Read what some of our customers say:

"Michael" H.

Community Non-Profit

"Ronald" B.

School District

Stacy W.

Medical Office

David K.

Retail Office

Anthony H.

Charitable Non-Profit

Lee W.

Lumber Company

Marc M.

Power Supply Reseller

Tim N.

Printing Equipment Reseller

Gloria S.

Credit Union

Brittany B.

Legal Organization

Kathi H.

Family Services

Ken G.

Financial Services

Check out a few of our Case Studies from actual ESI customers:

ESI Case Study: Automotive

ESI Case Study: Property Management

ESI Case Study: Retailer/Franchise

ESI Case Study: Religious Organization

Our Patents

Industry Awards

Systems

Devices

Applications

Integrations

Access

Client Testimonials

Talk to a Voice Expert

Award-Winning VoIP
Business Phone Solutions