Written by Claude Quiba Reviewed by James Macey Updated on 12 April 2023 On this page What is a business phone line? The types of business phone line Landline phone lines vs. VoIP phone lines The PSTN and ISDN switch off The best business phone lines 1. 8x8 2. RingCentral 3. Vonage How did we compare the best business phone lines? Verdict FAQs Expand Our site is reader-supported – by clicking our links, we can match you with a potential supplier, and we may earn a small commission for this referral. If you're wanting to bridge the gap between yourself, your team, business partners, and clients, then choosing the best business phone line is a must. Our team of in-house researchers found 8×8, RingCentral, and Vonage to be the best business phone line suppliers in the industry.Even with the emergence of smartphone, email, and chat technology, a business phone line remains at the top of the game by creating a network of connections with functionalities equipped for the business environment. In this article, we'll bring clarity to what a business phone line is, comparing the different types of business telephone lines, and explaining what the future holds for them.Expert Market's team of experienced researchers has been reviewing the top phone lines for business for years. So if you want our personalised advice, try our free quote comparison tool. Just answer a mini survey, and trusted business phone line providers will contact you with obligation-free quotes that are customised to your needs. Swipe right to see more 0 out of 0 backward forward Best overall 8×8 Best for customer service teams RingCentral Best for small businesses Vonage 4.7 4.5 4.4 Pricing £19 – £135 Pricing £7.99 – £29.99 Pricing £9 – £16.50 Key Features Onboarding supportCall queueRing groupsAnalyticsCustomisable call routingCall recording Key Features Voicemail to textHigh-definition (HD) voiceMulti-level auto attendantVisual voicemail and voicemail to email Key Features Onboarding supportCall queueRing groupsCall recordingCall monitoringAnalyticsWeb conferencing Get Quotes Get Quotes Get Quotes Get free, tailored quotes from the best phone line providers for your business Do you already use business VoIP? Yes No Just answer a few questions - it only takes a minute What is a business phone line?In the past, a phone line referred to the wire attached to your telephone (landline), which links you to a network that allows you to make and receive calls. Eventually, as businesses grew more complex, the limitation of only allowing one call per line became a problem.Thankfully, business phone lines no longer require a connection to a landline network to make a call — they now use the internet through a VoIP (voice over internet protocol) system. This allowed the telephone industry to develop various features suited to the business environment, such as accommodating multiple phone calls simultaneously, forwarding calls, and conferencing.Hence, a business phone line today refers to a telephone system, whether landline or VoIP, that enables you to perform multiple functions designed for business, including call queue call forwarding, voice and video conferencing. The types of business phone lineThere are three types of business phone lines today: public switched telephone network (PSTN), integrated services digital network (ISDN), and voice over internet protocol (VoIP).Public Switched Telephone Network (PSTN)The Public Switched Telephone Network (PSTN) was the original technology invented in the late 1800s. It's what you call a landline today—the copper telephone lines that run throughout your city to transmit analogue voice. Although we’re using modernised PSTN landlines, the principle behind its technology is essentially the same since its conception.The PSTN network is being switched off by December 2025 as it's outdated and expensive to maintain, find out why this is important for your business here.Integrated Services Digital Network (ISDN)PSTN's successor, the integrated services digital network (ISDN) launched in the late 1980s. It digitised the standard landline, enabling the simultaneous transmission of voice and data over copper PSTN wires. Compared to its predecessor, it offers businesses clearer, higher voice quality with less distortion and faster data transmission.Voice over Internet Protocol (VoIP)Finally, we have voice over internet protocol (VoIP), overtaking PSTN and ISDN connections in the business world. As the name suggests, voice over internet protocol (VoIP) refers to voice transmission over the internet instead of traditional phone lines.Since calls are conducted over the internet, VoIP eliminates physical barriers to communications. Your phone system can grow as your business scales. With everything on a single data network instead of separate phone lines, features like conference calls and call forwarding are made easier. It outperforms all other business phone lines, especially in efficiency and scalability. Landline phone lines vs. VoIP phone linesNow that we've defined what a business phone line is and its different types, let's go in-depth on the difference between landlines and VoIP lines, focusing on three key categories: price, functionality, and mobility.PriceYou won’t need a huge initial investment to set up a VoIP phone line. Since it’s a cloud-based system, you can choose not to invest in handsets because it can operate through smartphones and computers. You also don’t need to pay installation fees for wiring and telephone equipment.In contrast, telecom companies that provide landline services will charge an installation fee per phone line. Your expenses will increase as you add more phone lines. Likewise, landlines can only operate through analogue devices, so you will have to purchase and configure office phones in your office. Moreover, you have to add new wiring and phone jacks to your overall cost.FunctionalityVoIP lines have many features under their belt. Depending on your subscription choice, you can utilise tools like ring groups, call queue, and virtual receptionist. You can also automate the management of high call volumes, facilitate conferencing with multiple users, and forward calls.A traditional landline system requires a person to route call traffic, or you’ll need to upgrade to a pricier on-premise private branch exchange. Both landlines and VoIP offer voicemail. However, digital phone services provide voicemail-to-text or voicemail-to-email. Plus, you can read voicemail transcriptions on your mobile or desktop app.MobilityVoIP lines have nationwide coverage, some providers even offer services abroad. So, should you decide to transfer overseas, you don’t have to cut off your service. Simply inform your provider of your address change for continuous coverage anywhere that offers internet access.If you leave your landline provider's service area, you probably won't be able to keep it. You will have to transfer your number to a local provider whenever you travel abroad, or go into rural areas.Moreover, landline service requires a desktop or handset to make a call. VoIP makes use of apps to turn smartphones, computers, and tablets into business communication devices. The PSTN and ISDN switch-off: what do I need to know? With landline technology being unable to compete with VoIP's speed, flexibility, and quality, BT announced in 2017 that it will shut down its PSTN and ISDN networks by December 2025. PSTN and ISDN will completely phase out, ushering in an era of fully online telephony.If this is going to affect your business, read our guide on how to change your landline provider and get ahead of the switch-off. The best business phone linesWe recommend that you invest in VoIP phone lines rather than landlines because they are cheaper, flexible, and have significantly more features. Here are our three best business VoIP suppliers in the UK according to our research: 1. 8×8: Best overall business phone line supplier 8x8 4.7 Pricing £19 - £135 Get free quotes 8x8 review Quick overview Our best pick, 8x8, has a stellar overall rating of 4.7/5 in our analysis. All 8x8 plans come with unlimited domestic minutes. When you subscribe to the second cheapest plan, this will expand to unlimited international minutes to 14 countries. This will then upgrade to 48 countries on the X4 plan. Additionally, it supports number transfers across all pricing tiers, allowing you to keep your current business phone number while also getting call flexibility. Read more + Read less - Strengths Most comprehensive list of features Up to 500 video conferencing participants per meeting Various customer support channels Widest selection of pricing plans Weaknesses Expensive plans Mediocre customer review score Advanced outbound communication features (power dialer, predictive calling, and auto-dialer) are add-ons Pricing See more See less PlansStarting price Per user, per month. Billed annually. X2 £19 X4 £36 X6 £85 X7 £105 X8 £135 8×8 is our best overall business phone line supplier because it has the most extensive collection of communication tools, including ring groups, external video calling, and call-flow designer. It receives the highest features score in our analysis (4.6/5) with extensive outbound communication tools like set caller ID, custom call lists, and call conferencing with up to 500 participants per meeting. To maximise your time for client calls, you can even add power dialer, predictive dialling and auto dialer for an extra cost, making it the best choice for sales teams.Customer service is another strong suit, earning a perfect 5/5 in our research. You can quickly contact the 8×8 helpdesk via a user forum, online knowledge base articles, live chat, email, or phone. Best of all, it offers a 24/7 phone line and live chat, so you can call them around the clock. 2. RingCentral: Best for customer service teams RingCentral 4.5 Pricing £7.99 - £29.99 Get free quotes RingCentral review Quick overview RingCentral earns top scores in our research for scalability (4.9/5) and external connections (4.3/5). It also has the best inbound communication features, making RingCentral our top choice for small to medium businesses. In addition to being dependable, it also has a broad range of software compatibility and is adaptable enough to grow alongside your expanding company. Read more + Read less - Strengths Up to 97 CRM and 57 analytics integrations A wide range of call features in Premium and Ultimate plans Weaknesses Advanced outbound communication features require RingCentral Engage The bulk of integrations are only accessible on the Premium and Ultimate plans Pricing See more See less PlansStarting price Per user, per month. Billed annually. Essential £7.99 - £12.99 Standard £12.99 - £19.99 Premium £17.99 - £24.99 Ultimate £22.99 - £29.99 RingCentral is our best business phone line supplier for customer service teams because it offers the best set of inbound communication features, including a customisable greeting and virtual receptionist. You can even add ring groups and a call queue to manage the call traffic from customers. Plus, you can set your own schedule on when you want your phonline open for customer service,For as low as £7.99 per user per month, RingCentral offers a virtual receptionist, helping you direct callers to the appropriate department and allowing you to add business hours in case a customer wants to learn more about the company.If you work on a marketing team, you probably won't be as impressed by RingCentral. Unfortunately, it doesn't offer many outbound communications features, like power dialling or predictive dialling, making RingCentral unsuitable for outreach. You would have to buy the Ring Central Engage add-on to gain access to these outbound communication features. 3. Vonage: Best for small businesses Vonage 4.4 Pricing £9 - £16.50 Get free quotes Vonage review Quick overview Vonage scores a 4/5 in our feature analysis, offering over 50 communication features, such as voicemail-to-text, a call queue, and ring groups, to choose from and include in your plan. This makes it easier on your pocket because you only pay for the functionalities you need. This allows you to start on the cheapest plan with basic features, and scale up as your demands grow. Read more + Read less - Strengths Affordable plans A variety of inbound communication features Wide customer support channels Weaknesses Some basic features are for an extra cost No 24/7 live support Pricing See more See less PlansStarting price Per user, per month Select £9 Professional £12.50 Ultimate £16.50 Vonage is our best phone line provider for small businesses because it provides excellent third-party integrations at a reasonable price, scoring 3.8/5 for external connections and a solid 4.3/5 for pricing.Third-party integrations will boost the efficiency of your call centre agents by giving them access to information and tools across various platforms in a snap. With a better way to organise customer data, you'll be able to make calls faster and handle calls more efficiently.Vonage also scores a high 4.5/5 in our features analysis. Equipped with outbound communication tools, such as set caller ID, external video calling, custom call lists, it will help teams reach out to their leads and customers to boost relationships. As a result, Vonage is our best pick for small businesses that need an automated help desk for handling customer queries, such as solicitors. Get free, tailored quotes from the best phone line providers for your business Do you already use business VoIP? Yes No Just answer a few questions - it only takes a minute How did we compare the best business phone lines?Expert Market researchers thoroughly evaluated the best business phone lines to help you find the perfect telephone system for your business, using the following key criteria to assess each provider:Price – each plan's cost and value for your moneyIntegrability – the software's ability to integrate with other platforms, such as Salesforce, Slack, and GSuiteFeatures – the tools and capabilities that empower your inbound and outbound communications, internal conversations, agent management, and team collaborationCustomer Support – the customer support channels available, such as phone lines, live chat, and emailCustomer Score – the average consumer review scores across the most trusted review sites: G2, Capterra, Trustpilot, and TrustRadiusSecurity – the security measures the vendor enforces to protect your dataScalability – an aggregated score that assesses a product's ability to scale with your business's growthOnce our researchers collate all information and score each key category, we compute each business phone plan’s final scores and rank them. Verdict There's no doubt that VoIP lines are a better choice than landlines. They are much more flexible, allowing you to call from your smartphone or computer. Best of all, you can enjoy many features that are useful for call handling, management, and collaboration with your team. Because of this, PSTN and ISDN will soon switch off bringing telephony fully online.Our researchers chose 8×8 as the best overall phone line supplier because it offers the strongest list of features. RingCentral comes close, providing the best inbound communication features. This is followed by Vonage with excellent integrations at an affordable price.If you still can't decide which business phone line supplier to choose for your business, try our free quote comparison tool. Just answer a few questions about your team, and we will match you up with the best providers in the UK. They'll then be in touch with obligation-free quotes that are tailored to your needs. It's a quick and easy way to compare the right options for your business. FAQs What is VoIP? VoIP or Voice over Internet Protocol allows you to make and receive calls over the internet instead of your traditional copper phone lines. Is VoIP better than landline phone lines? VoIP is better than landline phones because it can cater to multiple calls on one business phone line. In addition, it grants you more features and capabilities than your traditional landline phones, including SMS, chats, and video calling. What's the difference between PSTN (analogue) and ISDN (digital) phone lines? A PSTN phone line, or analogue phone line, is suitable for those requiring a simple phone system. This is because it supports just one call at a time. If you want to receive more than one call at the same time, you’ll need multiple PSTN lines, and this will mean having multiple phone numbers.While this solution is fine for very small businesses with no more than a few employees, it soon becomes expensive when you need more than a couple of lines. You’ll also need a separate line for your internet.An ISDN phone line, or a digital phone line, is capable of doing far more. Firstly, it carries up to eight calls at the same time – this means there’s no need to invest in more than one phone line. Secondly, it can carry internet, voice, video, and fax data, and it even prioritises the voice data to ensure you benefit from the highest call quality.ISDN phone lines are the most common type of phone line, and provide a faster internet connection and download speed. However, these days, many businesses are choosing to switch to fibre lines, which provide an even quicker internet connection. What’s the difference between a hosted and self-hosted phone system? A hosted phone system, also known as a cloud phone system, is hosted offsite on a remote server, which is usually owned and maintained by your phone system provider. These phone systems are cheaper to install, and easier to manage.A self-hosted system is hosted by you, usually on a server inside your premises. This type of system is usually costly to set up, and requires dedicated IT expertise to maintain it and keep it updated. On the plus side, you can tailor self-hosted systems to your exact requirements, and choose when to update your system. How much does a business phone line cost in the UK? Depending on your choice of phone systems, hosted VoIP systems cost between £6 to £40 per user, per month, depending on the needs of your business. On the other hand, a self-hosted VoIP system can range between £600 to £800 per user. Meanwhile, the analogue office phone system costs around £99 to over £900. Read our guide to phone system prices to find more information. How many phone lines does a business need? The number of phone lines you need will depend on various factors, including your call traffic, the size of your company, and how many employees you have. Do I have to have a business phone line? A business phone line is essential because it offers features that will help you manage calls, supervise your agents, and collaborate with your team. It's also good for branding, as it adds professionalism to the way you handle customers. Written by: Claude Quiba Content Writer If you want insights into the best phone systems for your business, Claude Quiba will give you the lowdown on the latest in the industry. She's also a dreamer, a writer, and an autism advocate. Talk to her about art, coffee, or anything under the sun. But mostly, she's your go-to person when it comes to finding the best solutions for your team. Reviewed by: James Macey Senior Business Software Researcher James thinks all businesses can improve if they use the right technology. At Expert Market, he utilises his 4+ years experience as a researcher to offer specialised advice on a wide range of categories from CRM to Fleet Management.