Many of the best business phone systems remain to be an 
	  on-premise PBX. The most appropriate choice depends just as much 
	  on 
	  cost and needs 
	  as it does about the way you get your current phone service. And the 
	  facilities' infrastructure. If you receive your Internet and dial tone with 
	  a PRI circuit then you'll need a PBX capable of handling a T1/PRI. If you have 
	  four business lines you want to keep, then the phone system needs to 
	  include four FXO ports. If you need to replace an older, outdated PBX and 
	  require the use of existing older phone wiring, then a hybrid digital IP-PBX would 
	  represent 
	  a leading choice.
It's accurate the last few years have prompted many companies to determine that hosted cloud-based voice (UCaaS) services possessed distinct advantages. Most notably for small new businesses and office environments employing at-home and remote workers. Many sales associates and on-the-go employees need to connect as though they're in the office, and hosted services make that exceptionally easy. This trend has accelerated over the last few years, with employees expecting to work from home or remotely on some days.
More small businesses with less than 300 employees who acquired a phone system, bought a premise-based PBX.1 And 40% of new Unified Communication systems shipped globally were on-premises PBXs.
	  However, many companies continue to prefer an on-premise phone system, 
	  either a new one or as a replacement system. The 
	  onetime expense mitigates the open-ended monthly costs that come with 
	  hosted solutions. Many of these on-premise 
		  PBX phone systems are equally capable of supporting remote workers and 
	  incorporate advanced Omni-channel communication features. However, many 
	  business owners routinely merely call for an affordable basic phone system 
	  adequate for their situation. 
	  Over time, costs for an on-premise based PBX 
	  remain consistently lower than most hosted 
	  systems. Plus, the greater the number of phones in a deployment, the less 
	  time it is to recoup the initial outlay and curtail monthly 
	  expenses. Business have identified how easy it is to employ SIP trunking 
	  for their phone service resulting in significantly lower calling costs. Furthermore, there exists a significant range of diverse PBX 
	  systems that vary in price, features, and capacities, which favors business 
	  owners in obtaining an appropriate cost-effective solution. 
	  
Mitel 
	  offers exceptional communications solutions, both cloud based and 
	  on-premise. The MiVoice Connect system replaced ShoreTel after its 
	  acquisition and remains one of the top on premise IP-PBX solutions 
	  available. At its core is ShoreTel technology. It's a scalable, full-featured, flexible on site UC solution designed for an intuitive user 
	  experience with easy management. The Connect client allows users to 
	  access voicemail, directory, conferencing, transfer and other features 
	  from inside the office or on their mobile app.
		  
		  
PBXact, 
		  Sangoma's IP-PBXs are based on FreePBX. They deliver a robust IP-PBX appliance with lots of 
		  components and flexibility for just about any type 
		  of small to mid-sized company. Although most SIP compliant phones can 
		  be used, using Sangoma's S-series phones, which are designed 
		  exclusively for PBXact, delivers a complete package with Zero Touch 
		  installation. PBXact appliances range from small (25 users) all the 
		  way to enterprise models and offer the means to connect to traditional 
		  phone lines and a T1/PRI, in addition to using SIP trunks. 
		  Complimenting these solutions, Sangoma offers support making this 
		  UC appliance an excellent choice for those that want to use in-house 
		  personnel for its administration.
			
Cisco, known for their enterprise Unified Communications (UC) solutions, includes the Business Edition 6000 for companies with 25 to 1000 employees. Coming with a suite of preloaded, ready to activate UC solutions, the BE6000 offers easy expansion with apps that can be enabled including contact center, video conferencing, and Cisco Webex® Hybrid Services among others.
				  
Fortinet  
				  offers Unified Communication PBX solutions under FortiVoice with 
				  appliances sized for both small offices and enterprise-sized 
				  companies. Their IP-PBX servers offer various TDM connections, including a T/1 in the FVE-300E-T model. FortiVoice 
				  offers complete enterprise-class communication systems without 
				  requiring additional license fees or telephony cards. Some of the 
				  integrated 
				  features include auto attendants, auto-provisioning, 
				  line/extension appearance, ring groups, user privileges, call 
				  queue, call barge, and multi-location integration. 
		  
Zultys 
		  MX IP-PBXs are based on Open Standards and can 
		  use a broad range of 3rd party SIP-based IP phones. Server 
		  configuration can accommodate various TDM connections, including 
		  ISDN T1/PRI. The MX integrates voice, video, integrated Fax, Voice Mail, 
		  Contact Center, Presence, Instant Messaging, Zultys Mobile 
		  Communicator™, integrated MXconference™ and audio conferencing. Zultys, 
		  a pioneer in IP communications for twenty years, continue to receive 
		  industry recognition. The MX IP phone system earned a 2020 and 2023 Internet 
		  Telephony Product of the Year Award. Zultys Advanced Communicator 
		  (ZAC), a 2022 Unified Communications Product of the Year Award, brings 
		  together voice, chat, web conferences, file sharing, drag, and-drop call 
		  operations, and task management in one easy-to-use workspace.
		  
		  	
Switchvox 
			  E-series on-premise appliances matched with their 
			  D-series IP phones deliver a comprehensive UC solution for small 
			  to mid-sized companies. Currently owned and sold under Sangoma, Switchvox was 
			  developed by Digium, the creator and developer of Asterisk. With 
			  consistent, reliable performance, these Sangoma VoIP appliances, 
			  like the E525 and E510, 
			  integrate phone, fax, chat and web conferencing over SIP for a 
			  full featured communication solution.
 Switchboard, an intuitive web-based app, solves and integrates communications for customer 
			  service agents so they possess the efficient means to complete more 
			  functions improving service.
	  
Avaya's 
	  IP Office is one of the most popular unified communication (UC) 
	  on site PBXs in the world. Providing flexible solutions, their on premise 
	  IP Office 500 PBX solves hybrid deployments (digital and IP) with the 
	  ability to migrate from one to the other when the time is appropriate. 
	  Moving from digital to IP to cloud-based, Avaya's IP Office includes an 
	  easy path. With the capacity to connect to any phone service (FXO, T1/PRI, 
	  SIP) it's a PBX that works for just about any environment, especially in 
	  mixed use facilities that require the use of existing phone cabling. 
		  
		  
Allworx 
		  Connect is a third generation, feature-rich VoIP communication 
		  platform that offers 
	  IP connectivity. Servers range from the 320 for a small office up 
		  to the 731 capable of handling 250 users. The 324 and 320, for up to 
		  20 users, can come with four FXO ports for those that want to keep 
		  some traditional phone lines. The 731 includes a T1 port 
		  for those using a PRI 
		  circuit. An all-inclusive PBX system, the Allworx Connect remains a 
		  top choice for an on-premise PBX that has most of the features any 
		  business would want.
		  
NEC 
		  is a major worldwide manufacturer of communications equipment that 
		  offers both affordable small systems and enterprise solutions. Their 
		  SL2100 remains an extremely practical, full featured PBX phone system 
		  with VoIP capabilities that would compliment a broad range of 
		  businesses. Choosing the NEC SL2100 is a cost-effective solution that 
		  can be installed in just about any environment (Analog, PRI, IP) and 
		  ensures your company will remain ahead of the technology curve. NEC 
		  recently announced an end to their on-premise business phone systems 
		  outside of Japan, including the SL2100 and SV9100.
		  
		  
Grandstream's 
		  UCM IP-PBXs can connect to your existing traditional phone lines or your Internet 
		  connection using VoIP (or both). Based upon open source Asterisk and 
		  SIP IP phones, the UCM offers a robust Unified Communication system 
		  without license fees. The impressive servers come with a carefully 
		  designed interface that can integrate voice, video, facility access 
		  and mobility communications. When matched with Grandstream endpoints, 
		  configuration and administration becomes relatively straightforward. 
		  Support is included from Grandstream.
It's easy to become overwhelmed with all the information obtainable. A preferable option might be to respond to a few straightforward questions and then compare best-price quotes.
	  
Each of our on-premise PBX business phone system choices 
	  sustains high customer reviews and receives notable industry awards. 
	  Additionally, each of these systems has numerous installations and are 
	  consistent 
	  and durable performers. Companies have likewise recognized that investing 
	  in an on-premise PBX does not limit them from employing VoIP. It's 
	  straightforward to gain all the advantages that come with low cost 
	  SIP trunking.
Both the Mitel MiVoice 
	  Connect (formerly ShoreTel) and the Cisco Business Edition 6000 remain excellent choices 
	  where cost is not the decided limiting factor. Switchvox (formally Digium) offers another 
	  high-end option for companies that retain a capable IT staff. Avaya through 
	  innovation remains a prominent solutions provider. Their hybrid IP-Office 
	  continues as a consistent option that can accommodate a broad range of varied 
	  installation requirements.
NEC has developed a reputation for reliable, robust affordable 
	  solutions. With their exit from on-premise systems, savvy buyers can find 
	  bargains. And for 
	  businesses that desire an affordable VoIP appliance with innovative technology, Zultys 
	  delivers an award-winning system. Likewise, Sangoma's PBXact and Grandstream's UCM
	  serve 
	  as impressive 
	  communications solutions, especially for those that want to self-manage
their 
	  systems in house.	  
FortiVoice, part of Fortinet, represents an 
	  attractive choice for many companies.
Specifically those that at present use their 
	  first-rate security devices. And Allworx delivers an advanced IP system
 
	  that has seen numerous small business deployments. Each of the chosen PBX companies, some of which 
	  also offer
cloud-based services, should continue to deliver outstanding communication 
	  solutions into the future, ensuring product certainty.
1More companies selected a new on-premise PBX than UCaaS services. PbxMechanic News & Commentary In 2024, 40% of new Unified Communication systems shipped globally were on-premises PBXs, and half of all installed systems are premise-based.
Cisco BE6000 Brochure Switchvox Brochure Mitel MiVoice Connect Brochure Avaya IP Office 500 Brochure Grandstream UCM Brochure
PBXact Brochure NEC SL2100 Brochure FortiVoice Brochure Allworx Brochure Zultys MX Brochure
Users that decide to switch to an on-premise PBX from a cloud-based solution routinely want to know if they can use there own IP-phones. Learn more here: Best On-premise IP-PBX Phone Systems if you Own IP Phones
See how using a SIP trunk with your PBX lowers costs. Using a SIP trunk with an on-premise PBX
Find out which are best cloud PBX phone companies. These are the top rated hosted VoIP providers: Best Cloud PBX Companies
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