Business Phone Line UK 2026: Types, Costs & How to Choose the Right One

Every business needs a reliable way for customers, suppliers and partners to reach them — and a business phone line remains the backbone of professional communication in 2026. But the landscape has changed dramatically. Traditional copper landlines are being switched off, cloud-based alternatives have matured, and the options available to UK businesses are wider than ever.

Whether you are setting up your first business phone line, expanding an existing system or preparing for the 2027 PSTN switch-off, this guide covers everything you need to know — types, costs, features and how to choose the right solution. If you already know you want VoIP and want to compare providers, our guide to business phone line providers in the UK is a useful companion.

What Is a Business Phone Line?

A business phone line is a dedicated telephone line used for commercial purposes. Unlike a residential phone line — which is designed for personal use — a business phone line is set up under a company name, typically comes with enhanced features and service-level agreements, and is treated differently for tax purposes.

The core differences between business and residential phone lines include:

• Features: Business phone lines include call management features such as auto-attendant, call forwarding, hunt groups and voicemail to email. Residential lines offer basic calling and little else.
• Service-level agreements: Business line providers guarantee faster fault resolution — often within hours rather than days.
• Tax treatment: The cost of a business phone line is a fully deductible business expense, and VAT-registered businesses can reclaim VAT on line rental, call charges and equipment.
• Number presentation: Business lines let you present a geographic number, national 03 number or freephone 0800 number — giving customers confidence they are dealing with an established company.
• Scalability: Business phone systems are designed to grow. Adding extensions, lines and features is straightforward.

For decades, a business phone line meant a physical copper wire from the BT exchange to your premises. In 2026, that definition includes VoIP lines delivered over the internet, SIP trunks and mobile-based solutions. The copper era is ending — Openreach will switch off the PSTN by January 2027 — but the need for a professional, reliable business phone line is as strong as ever.

Types of Business Phone Lines in 2026

There are four main types of business phone lines available in the UK today. Each has different strengths, limitations and costs, and the right choice depends on your business size, budget and working patterns.

Traditional Landlines (PSTN/ISDN)

A traditional business landline uses the Public Switched Telephone Network — the copper wire infrastructure that has served the UK since the Victorian era. PSTN lines carry analogue voice signals, while ISDN lines carry digital signals over the same copper, supporting multiple simultaneous calls.

For decades, PSTN and ISDN were the only options for business phone lines. They are reliable and work independently of your internet connection. However, the technology is now at end of life.

Critical point: Openreach stopped selling new ISDN lines in September 2023 and is switching off the entire PSTN by January 2027. If you are still running traditional landlines, you must migrate within the next twelve months. New businesses should not install PSTN or ISDN lines under any circumstances.

Traditional landlines also lack the features modern businesses expect — no video calling, no call analytics, no CRM integration and no remote working support. Even basic features like call recording require expensive bolt-on hardware.

For a detailed look at why the old network is closing and what it means for your business, read our guide on preparing your business for the 2027 landline switch-off.

VoIP Phone Lines (Cloud/Hosted)

Voice over Internet Protocol (VoIP) is the modern replacement for the traditional business phone line. Instead of sending voice over copper wires, VoIP converts speech into digital data packets and transmits them over your broadband connection.

Hosted VoIP — also called cloud VoIP — runs the entire phone system in secure data centres rather than on hardware in your office. You plug in IP handsets or install a softphone app, and everything works through your existing internet connection.

This is what the vast majority of UK businesses should be choosing in 2026. The advantages over traditional business phone lines are substantial:

• Lower cost: Plans start from as little as £5 per user per month, with UK calls typically included and no PBX hardware to buy or maintain.
• Rich features as standard: Auto-attendant, call recording, voicemail to email, call analytics, CRM integration and video conferencing are built in.
• Work from anywhere: Staff can make and receive calls on their business number from any device, anywhere with an internet connection.
• Instant scalability: Add or remove users in minutes through an online portal — no engineer visits, no new wiring.
• HD voice quality: Wideband audio codecs deliver noticeably clearer calls than analogue landlines.
• Future-proof: VoIP replaces the PSTN. Choosing it now means you are already prepared for the 2027 switch-off.

Our hosted VoIP for business guide covers the technology in depth, including how to evaluate providers and what to look for in a plan.

SIP Trunking

SIP (Session Initiation Protocol) trunking is a middle ground for businesses that have already invested in on-site PBX hardware. A SIP trunk connects your existing phone system to the internet, replacing the ISDN or analogue lines that currently feed it.

You keep your existing handsets, extensions and call routing — but calls travel over broadband instead of copper. SIP trunks are sold per channel (each channel supports one concurrent call), and pricing is competitive with hosted VoIP.

SIP trunking makes sense if you have a modern IP-PBX with years of useful life remaining. However, you still maintain the on-site hardware yourself and miss out on many cloud-based features. For most businesses, hosted VoIP is the better long-term choice.

Mobile-Only

Some businesses — particularly sole traders, freelancers and field-based workers — use a business mobile as their primary business phone line. With the right contract, a business mobile gives you a dedicated number, inclusive calls and data, and the flexibility to work from anywhere.

A mobile-only approach works well when you are a one-person business, spend most of your time away from a fixed location and do not receive high volumes of inbound calls.

The limitations become apparent as you grow. Mobiles lack professional features like auto-attendant, hunt groups and call queues, and customers calling a mobile number may perceive your business as less established.

Many businesses use a combination — a VoIP system for the office with business mobiles for staff on the move. Connection Technologies can help with both as an authorised VoIP provider and O2 Select Partner for business mobiles.

Business Phone Line Costs in 2026

The table below compares the four main business phone line options across the cost metrics that matter most.

Cost Factor	Traditional Landline	Hosted VoIP	SIP Trunking	Mobile-Only
Setup cost	£100–£150 per line + PBX £2,000–£10,000	£0–£100 per handset (or free with softphone)	£0–£500 (configuration only)	£0–£50 per handset (often free on contract)
Monthly cost per line/user	£25–£45	£5–£15	£5–£10 per channel	£10–£30 per SIM
UK call costs	Inclusive or per-minute (10p–15p to mobiles)	Usually inclusive (landline and mobile)	Per-minute or bundled	Usually inclusive
Features included	Basic (voicemail, caller ID)	Comprehensive (auto-attendant, recording, analytics, video)	Depends on PBX capability	Basic (voicemail, call divert)
Contract length	12–36 months	1–24 months	1–24 months	12–36 months
Maintenance costs	£80–£200/month (PBX contract)	£0 (managed by provider)	You maintain the PBX	£0

Hosted VoIP consistently delivers the lowest total cost of ownership, especially when you factor in the absence of hardware maintenance, engineer call-outs and per-minute call charges. If you are looking for a business phone line that maximises value, VoIP is the clear winner.

For businesses that also need broadband, bundling your phone system and internet connection can reduce costs further. Our guide to business phone and broadband bundles explains the options.

The 2027 PSTN Switch-Off: What It Means for Your Business Phone Lines

If your business currently uses traditional landlines, this is the most important section of this guide. The UK’s telephone infrastructure is undergoing its biggest change in over a century, and every business with a business phone line is affected.

What Is Happening?

BT Openreach is switching off the PSTN — the copper wire system that has carried phone calls since the 1800s. The shutdown will be complete by January 2027. Every analogue phone line, every ISDN connection and every piece of equipment that relies on the copper network will stop working.

This is not a proposal — it is a confirmed programme already well underway. Openreach stopped selling new ISDN lines in September 2023, and exchanges across the country are being migrated on a rolling basis.

What Does This Mean for Your Business?

• Your traditional business phone lines will stop working. PSTN and ISDN lines will be disconnected when your local exchange is migrated — or by January 2027 at the latest.
• You cannot renew your existing contract. Once your current agreement expires, there will be no like-for-like replacement on the old network.
• You must migrate to an IP-based alternative. For most businesses, this means hosted VoIP. For those with existing PBX hardware, SIP trunking is an interim option.
• Number porting is available. You can keep your existing business phone numbers when you move to VoIP.

What Should You Do Now?

If you have not started planning your migration, act now. Leaving it late risks longer lead times, delayed number porting and service interruptions. Our guide on preparing your business for the 2027 landline switch-off walks through every step.

How to Choose the Right Business Phone Line

Choosing the right business phone line comes down to understanding your specific requirements. Here are the key factors to consider.

Number of Employees and Lines Needed

A sole trader has very different needs from a 50-person office with a reception desk, sales team and support department. For one to three people, a mobile or simple VoIP plan may suffice. Larger teams need multiple extensions, call routing and simultaneous call capacity.

Remote and Hybrid Working Requirements

If any staff work from home or travel regularly, a traditional business landline tied to a single desk will not work. VoIP gives every team member full phone system access from any device, anywhere — non-negotiable for most UK businesses in 2026.

Existing Infrastructure

VoIP requires a stable internet connection — each concurrent call uses roughly 100 kbps. Standard fibre broadband handles this easily, but if your premises has poor connectivity, upgrade your broadband first. Businesses with an existing on-site PBX can use SIP trunking as a bridge.

Budget Considerations

Traditional landlines carry high upfront costs (PBX hardware) and high ongoing costs (line rental, maintenance, call charges). VoIP has low or zero upfront costs and predictable monthly per-user pricing. Consider total cost of ownership over three to five years, not just the headline price.

Feature Requirements

Do you need call recording for compliance? An auto-attendant to route callers? A mobile app for staff on the move? CRM integration? Video conferencing? List your must-have features before comparing providers.

Growth Plans

If you expect to hire, open new locations or expand into new markets, choose a business phone line that scales without friction. VoIP lets you add users in minutes. Traditional landlines require engineer visits and new wiring — a process that can take weeks.

Business Phone Line Features to Look For

Modern business phone lines — particularly VoIP systems — come with a rich set of features that were once reserved for large enterprises with expensive PBX hardware. Here are the features worth prioritising.

• Auto-attendant and IVR: Greets callers with a professional message and routes them to the right department. IVR adds multi-level menus. Even small businesses get the polished image of a larger organisation.
• Call forwarding and routing: Route calls based on time of day, department or staff availability. Forward to mobiles, home phones or other offices seamlessly to reduce missed calls.
• Voicemail to email: Messages are automatically transcribed or sent as audio attachments to your inbox — read or listen from anywhere without dialling in.
• Call recording: Record calls automatically for training, compliance and quality assurance. Cloud-stored recordings are searchable and accessible from any device.
• Mobile app and softphone: Turn your laptop, tablet or mobile into a fully functional business phone. Make and receive calls on your business number from anywhere — the feature that makes hybrid working practical.
• Video conferencing: Many VoIP platforms include built-in video, eliminating separate subscriptions to tools like Zoom or Teams.
• CRM integration: Connect to Salesforce, HubSpot, Microsoft Dynamics and others so incoming calls display customer records and call logs are saved automatically.
• Hunt groups and call queues: Ring multiple phones simultaneously or in sequence until someone answers. Queues hold callers with music or messages until an agent is free — critical for sales and support teams.

All of these features come as standard with Connection Technologies’ HyperCloud hosted VoIP from just £5 per user per month. Request a free quote to see the full feature list for your business.

Setting Up a Business Phone Line: Step by Step

The process is straightforward with the right provider. Here is what to expect.

Step 1: Assess Your Needs

List how many users need a phone line, what features are essential and how your team works (office-based, remote, hybrid or field-based). Consider your call volumes and whether inbound or outbound calling dominates. This assessment shapes every decision that follows.

Step 2: Check Your Broadband

Each concurrent VoIP call uses approximately 100 kbps. A 10-person office with five simultaneous calls needs just 500 kbps — well within the capability of any standard business broadband connection. If your broadband is unreliable, upgrade before switching. Our guide to business phone and broadband bundles can help.

Step 3: Choose a Provider

Look for transparent pricing, inclusive UK calls, a clear SLA, responsive UK-based support and the features your business needs. Avoid long lock-in contracts — the best providers offer flexible terms. Our comparison of business phone line providers can help you evaluate options.

Step 4: Port Your Existing Number

Your existing business phone numbers can be transferred to your new provider. Porting typically takes five to ten working days. Your provider handles the paperwork — you provide your current account details and authorise the transfer.

Step 5: Configure Your System

Your provider sets up call routing, auto-attendant greetings, hunt groups, voicemail, extensions and integrations. With hosted VoIP, this is all done remotely — no engineer visit required.

Step 6: Go Live

On the agreed date, your new business phone line goes live. If you are porting a number, it switches over seamlessly. From this point, you manage your system through an online portal — adding users, changing settings and viewing call analytics whenever you need to.

Why Choose Connection Technologies for Your Business Phone Lines?

Connection Technologies is an independent UK business telecoms broker. We recommend the business phone line solution that genuinely fits your needs — not the one that earns us the biggest margin.

• Independent advice: We work with the UK’s leading telecoms networks and compare options on your behalf.
• HyperCloud Hosted VoIP from £5/user/month: Our HyperCloud platform delivers enterprise-grade VoIP with inclusive UK calls, HD voice, softphone apps, call recording, auto-attendant and CRM integration.
• UK-based support — 45-second average answer time: A real person in the UK picks up the phone. No overseas call centres, no chatbot runarounds.
• Free number porting: We transfer your existing business numbers to your new system at no extra cost.
• PSTN migration expertise: We have migrated hundreds of UK businesses from legacy landlines to VoIP with zero disruption.
• Scale up or down instantly: Add or remove users in minutes through your online portal. Your bill adjusts automatically.
• Business mobiles too: As an O2 Select Partner, we provide business mobile contracts — phone system and mobiles from a single supplier.

Frequently Asked Questions

How much does a business phone line cost?

A traditional business landline costs £25–£45 per line per month, plus call charges and PBX maintenance. A hosted VoIP business phone line costs £5–£15 per user per month with UK calls typically included. For a ten-person office, VoIP works out at roughly £50–£150 per month compared to £350–£650 for traditional landlines.

Can I keep my existing business number?

Yes. Your existing geographic, non-geographic and freephone numbers can all be ported to your new provider. The process typically takes five to ten working days with no interruption to service.

What is the difference between a business phone line and a residential one?

A business phone line comes with enhanced features (auto-attendant, call routing, call recording), faster fault-repair SLAs and professional number presentation. The full cost is tax-deductible. A residential line offers basic calling, slower support and limited deductibility.

Do I need a landline for my business in 2026?

No. A traditional copper landline is no longer necessary and is being phased out ahead of the January 2027 PSTN switch-off. Most businesses are better served by a VoIP business phone line, which delivers superior features, lower costs and full remote-working flexibility. Our VoIP vs landline comparison explains the differences in detail.

What happens to my business phone line when the PSTN switches off?

If your business phone line runs on the copper network (PSTN or ISDN), it will stop working by January 2027 at the latest. You need to migrate to VoIP or SIP trunking before that date. Your phone numbers can be ported to the new system, so customers will not be affected.

How many phone lines does my business need?

With traditional landlines, you need one physical line per concurrent call. With VoIP, each user gets their own extension and the number of concurrent calls is limited only by your broadband bandwidth — a standard connection handles dozens of simultaneous calls. You simply pay per user rather than per line.

Can I use my mobile as a business phone line?

Yes, and for sole traders this can work well. The drawback is that mobiles lack professional features like auto-attendant, call queues and hunt groups. A better approach for growing businesses is a VoIP system with a mobile app — you get a full-featured business phone line that works on your mobile, desk phone and laptop simultaneously.

How long does it take to set up a business phone line?

A new VoIP business phone line can be working within 24 to 48 hours with a new number. If you are porting an existing number, allow five to ten working days. Connection Technologies manages the entire process from start to finish.