Multi-line phone systems are an ideal solution for businesses looking to expand calling capacity without moving to larger and more expensive solutions. These systems use a variety of technologies. For example, a multi line phone might use Private Branch Exchange (PBX), key system unit (KSU), or Voice over Internet Protocol (VoIP). Each has its own advantages. However, PBX and VoIP are the two most common today. In addition, all system options allow you to accept more calls from a single phone. That means employees can put callers on hold, can switch to another incoming call, and dial internal or external numbers from a single phone.

Most multi line phone systems for small business come with 2 or 4 lines. Most also support up to 8 additional phones. Larger systems might support up to 12 lines. However, as this guide is for small business, it covers 2- and 4-line phone systems.

Best 2 Line Phone Systems

The table below gives a quick price comparison of the top 2 line phone systems for business.

Model	Call Transfer	Speaker System	Voicemail	Cordless	Price
AT&T ML17939	No	Yes	Yes	No	$79.99
Panasonic KX-TG9542B	No	Yes	Yes	Yes	$199.99
Poly VVX 150	Yes	Yes	Yes	No	$40-$95
VTech DS6151	Yes	Yes	Yes	Yes	$79.95

AT&T ML17929 2-Line Corded Telephone

AT&T’s ML17929 is a 2-line corded phone with most of the bells and whistles you could want. Additionally, this is one of the best multiple line business phones for those looking for conferencing.

Features include:

• 3-Way conferencing supported
• Corded phone but supports headsets
• Voicemail with display
• Caller ID / Caller Waiting for up to 100 names/numbers
• A maximum of 2 lines supported/ not extendable
• Integrated 100-number phonebook with 9-button speed-dial
• Duplex speaker system with volume control

AT&T ML17929 2-Line Corded Telephone Link

Panasonic Link2Cell KX-TG9542B

Panasonic’s Link2Cell KX-TG9542B is a perfect 2-line phone systems for small business. You get a 2-line system. You also sync up to 4 smartphones – so office workers can answer the phone in one place during the workday.

Features include:

• Link up to 4 cell phones with text message alerts
• Includes a corded base + wireless second phone
• Headset jack
• Speaker system
• 3-Way conferencing
• 2 Answering machines
• Caller hold and caller ID, with music on hold
• Battery backup

Panasonic KX-TG9542B product link

Poly VVX 150 2-Line IP Desk Phone

The Poly VVX 150 is one of the best 2-line phones if you’re on a budget. While cheap, it delivers all-around performance and quality in a sleek outer casing.

Features include:

• 2-Line phone with IP support
• Headset jack
• Supports 3-way conference calls
• Call hold, transfer, forward, and end buttons
• Voicemail support
• Caller ID + Speed Dial function
• Call timer
• Programmable keys

Poly VVX 150 product link

VTech DS6151 2-Line Cordless Phone System

The VTech DS6151 multi line business phone offers a wide range of features for a low price. It’s also a top choice for local conferencing, with fully interconnected handsets.

Features include:

• 2-line business phone
• Supports up to 12 local handsets with call transfer between them
• Supports conferencing with one external line + 4 local handsets
• Voicemail
• Call waiting / hold
• Phonebook for up to 50 contacts
• Page/handset locator function

VTech DS6151 2-Line Cordless Phone System product link

Best 4 Line Phone Systems

The table below gives a quick price comparison of the top 4 line phone systems for business.

Model	Call Transfer	Speaker System	Voicemail	Cordless	Price
AT&T 1070	Yes	Yes	Yes	No	$129.95
XBLUE x16	Yes	Yes	Yes	No	$99.99
RCA U1000	Yes	Yes	Yes	NO	$149.99
Cisco SPA504G	Yes	Yes	Yes	No	$189.99

AT&T 1070 4-Line Expandable Corded Phone System

The AT&T 1070 is probably the most recommended 4 line phone systems for small business. It’s also easy to see why with a host of features and expandable functions.

Features include:

• Expandable from 1-4 lines
• Add-on up to 16 units on the same system
• Seamless call transfers
• Speakerphone and headset support
• 3-party conferencing
• Auto line selection with line-use indicators
• 200 name/number caller history

AT&T 1070 4-Line Expandable Corded Phone System link

XBLUE x16 Small Office Phone System

The XBLUE x16 is one of the best 4-line phone systems if you want regular phone lines and VoIP. In fact, XBLUE supports up to 6 traditional lines and up to 16 internet phones.

Features include:

• Supports 1-6 phone lines + 16 Internet Phones
• Voice Intercom with call forwarding & alerts
• Call Recording
• 3-Way conferencing
• 12 programmable buttons
• Forward calls to a cellphone
• Automated receptionist

XBLUE x16 Small Office Phone System link

RCA U1000 Unison 4-Line Expandable Phone System

The RCA U1000 Unison expands to support up to ten multiple line business phones. The system is also one of the best for offices looking for conferencing support.

Features include:

• 4-line business phone with a system expandable to 10 phones
• 6-way conferencing
• 99 name/number caller ID/phonebook
• Call waiting, transfer, hold functions
• Up to 200 minutes of recorded voicemail
• Integrated music on hold & digital receptionist
• Do Not Disturb mode

RCA U1000 Unison 4-Line Expandable Phone System link

Cisco IP Phone SPA504G

Cisco SPA504G offers more technical capabilities than any of the multi line office phones on this list. For example, with 2 SIP registrations, port switching, and Power over Ethernet capability, this phone is high tech.

Features include:

• 4-line phone system
• 3-way conferencing
• Call transfer with blind or attended transfers
• 60 number and name call history with redial functionality
• Anonymous caller blocking
• Web server for security configuration & settings
• Password-protected administration with security

Cisco SPA504G Product link

Benefits of Multi-Line Phone Systems

Multi-line phones are essential as you start to scale. This is especially true if you have a telemarketing or sales line – where you’ll frequently expect to have more than one person answering the phone. With a single line, if one person calls, anyone else who calls is dropped. Multiple lines allow you to offer call-holding, to accept multiple calls at once, and to transfer calls between handsets with some phones.

• Multiple line business phones reduce costs per line by up to 60%
• Multi-line systems allow one receptionist or telemarketer to accept more calls
• Reduced wait time and drop-off time improves customer satisfaction
• A multi-handset system allows you to supply every desk with a handset
• Most support call conferencing
• Extras like voicemail, call forwarding, and hold music can save you money on other services
• Many systems scale up, meaning you can simply add on more units

Essentially, using multiple line business phones can save your organization money. It also offers convenience and scalability. Both can improve the customer experience, while boosting office productivity. And, it’s a lot cheaper than simply installing more phones at every desk.

Multi Line Phone System Features

Multiple line office phones offer a wide range of features. However, not all offer the same features. That means it’s important to decide what you need and to compare.

Conferencing

Audio conferencing allows you to connect to 1 or more external lines with internal lines. Most phones support 3-way conferencing. That means you plus two other inbound lines. Others support more. However, you’ll normally need larger phone systems to support more than 6. Additionally, some phones offer multiple handsets. Here, you can allow individuals to conference from their own office to reduce total noise interference.

Call Transfer

Call transferring allows you to send a call from one phone to another. This might mean from one line to the next. It might also mean from one phone or handset to the next. In some cases, you can also get call forwarding and call transfers to your mobile phone.

Caller ID/Phonebook

Most business phones offer a caller ID and phonebook. In some cases, you’ll get 30 names and numbers. In other cases, you can get well over 200. These allow you to quickly make calls. Most also offer re-dial, for up to 100 previous callers. That can save time when getting in touch with leads and prospects. It also allows you to make calls more quickly, without typing in numbers every time.

Call Recording

Integrated call recording is great for customer service, quality of service recordings, and for interviewing. Having it built into your phone means you get higher quality recordings. Plus, you won’t have to pay for a secondary service.

Speakers

A speaker system allows you to take calls without holding the handset. This is ideal for conferences. It’s also ideal when quickly switching between calls.

Headset Jacks

Headset jacks are a must-have for most commercial phone lines. If callers don’t have an office to themselves, a headset enables quiet calls.

Digital Receptionists

Digital receptionists can help to filter callers, so that they end up at the correct phone, line, or handset. However, these vary in complexity. For example, the simplest just greet callers and tell them there is a wait. Others allow you to set up a selection menu.

Programmable Buttons

Programmable buttons can be set as speed dial buttons, as line buttons, or to forward calls to another extension or call. Button functions vary considerably depending on other phone features.

Voicemail

Voicemail is a critical function for many phones. However, multiple line office phones have more complicated voicemail. For example, some have a voicemail box per line. Others have just one to share.

Digital Displays

A digital display shows incoming calls, phone numbers, busy lines, and other data. For example, some phones show which line you’re calling on. Others show how long the call is running. Some even time every open call on the phone. Different phones offer many different features. However, you always get call visibility and caller visibility.

VoIP Support

Some business phones support IP and VoIP. These allow you to connect Sip trunking services. You can also connect call services like RingCentral, Google Phone, or Skype to the phone. That allows you to take internet calls on your actual phone. This can save a great deal of money if you need more lines. Additionally, it greatly decreases costs if you work with international clientele.

How To Compare Multi-Line Phones

In most cases, you should look at budget, scaling, and future usage. In addition, you want to know which features are important. For example, if you need 2 lines now but are scaling, you might want to choose a 4-line phone.

• How many lines do you need? A good rule of thumb is users per desk plus 2. So if you have 2 people taking calls at a desk, you’d want a 4-line system.
• How many phones do you need? Small offices can get away with one multi-line system with added handsets. In other cases, you might want a phone per desk or even per person if you’re doing telesales.
• What features do you need? For example, some are very obvious. E.g., you need call forwarding and VoIP support. In other cases, it might require thinking about how and when you’ll use the phone.

Budget is likely also a concern. However, most phone systems are relatively affordable. Additionally, most manufacturers offer discounts for bulk purchases.

How Does a Multi-Line Phone System Work?

Multi-line phone systems include Key System Unit (KSU) and Private Branch Exchange (PBX) phones. In most cases, you can also get a VoIP or digital system instead.

Most small business multi-line systems are KSU. However, with digitization, there are actually very few differences between them.

Traditional System – You simply set up two phone lines with the phone company. You connect both to the phone via the black and yellow wires on the phone. You may need a line splitter to support this.

KSU – Incoming calls are processed by a central device. In small business multi-line systems, that’s normally the phone. Calls are pushed to lines based programming or availability. Some also have complicated onboard processors. This allows you to set up larger outgoing calls.

PBX – PBX is like setting up your own network. For example, like a Local Area Network. You can set up internal and external lines. So, you can accept multiple external calls. However, you can also dial extensions to call colleagues at their desks. Most small businesses do not use PBX.

VoIP – VoIP systems are increasingly popular because they cost less. However, they are less reliable and more reliant on the internet. Here, you connect the phone to an Internet number. Calls are forwarded to the phone’s onboard computer and processed just like a normal call. This allows more versatility. Additionally, there are normally very few limits to how you set up the software.

Next Steps

There are dozens of different features and options to choose from. This list of the top multi-line phone systems for your business should be a good place to start. However, this list is aimed at small businesses. If you need more lines, you’ll want to look at a VoIP or a 6–12-line system instead.

Hopefully, this helps you choose the right multi-line phone system for your business.