Gamma PhoneLine+ : Landline Replacement for Small Businesses

PhoneLine+ is Gamma's cloud-based telephony service for micro and small businesses, the "we've had the same landline for 20 years and BT just told us it's going away" crowd. With the UK PSTN switch-off now on the January 2027 horizon, it's one of the most common fits we deploy for sole traders, small practices, and any business that doesn't need a full PBX but does need to keep their number and add some modern features along the way.

What PhoneLine+ is

A fully cloud-based, app-first business phone line. Replaces a traditional copper landline over broadband (or mobile data) with a softphone experience that runs on phones, desktops, and web browsers. You keep your existing business number (port it in) and get a handful of features that a classic landline never had, voicemail-to-email, SMS, WhatsApp, call notes, and so on.

Crucially, it's not a full PBX. Think of it as a modern, smarter single number (or small handful of numbers) rather than a full phone system with queues, call recording, wallboards, and agent licensing. If you need any of that, Gamma's Horizon or something like 3CX is the better fit.

Who it's designed for

In Gamma's own language: "micro-sized businesses." In practice, we find it lands well for:

• Sole traders who need a business number separate from their mobile
• 2–10 person professional firms (solicitors, accountants, consultancies) that want a landline-equivalent number with modern routing
• Home-based businesses moving off a BT residential-line-used-for-work
• Multi-location micro-businesses, one number ringing on several staff devices
• Firms replacing a legacy analogue line ahead of the PSTN switch-off

Where it's not the right answer: anything with more than ~15–20 users, contact-centre style work, or a need for tight CRM integration.

Features, what you actually get

Multi-device calling

The same number rings everywhere:

• iOS and Android mobile apps
• Windows and Mac desktop apps
• Web browser client
• Physical IP desk phones (Yealink, etc.)
• Legacy analogue phones via an ATA adapter, useful if a client insists on keeping their old phone

Staff can take a call on their mobile, hand off mid-call to a desk phone, and keep talking. No more "let me call you back from the office."

Number handling

• Number portability, bring your existing business number
• Hunt groups, one number rings multiple users, linear (one after another) or simultaneously
• Time-based routing, different destinations in/out of hours
• Interactive voice menus (IVR), "Press 1 for sales" with custom keypress options
• Multiple outbound caller IDs, show the main switchboard or a direct dial depending on context

Messaging and voicemail

• Voicemail-to-email (audio attached, no need to dial into a voicemail box)
• Two-way SMS from your business number
• WhatsApp Business integration, incoming and outgoing WhatsApp chats handled inside the same app
• Activity Feed, single timeline of calls, voicemails, SMS, and WhatsApp across the team
• Call Notes, jot down details during a call, attached to the call record

Mobile-first extras (Anywhere tier)

• eSIM integration, your PhoneLine+ number runs as a second eSIM on the user's smartphone, so it rings through the native dialler, not an app
• Works over mobile data without needing Wi-Fi at every site

The three tiers

Gamma sell PhoneLine+ in three editions, priced per user per month. The key differences:

Standard, the entry tier

• Core calling from any device (mobile, desktop, web, IP handset, ATA)
• Voicemail-to-email
• Call forwarding
• Plug-and-play provisioning
• For: the simplest "one number, one or two users, just works" scenarios

Office, adds routing features

Everything in Standard plus:

• Hunt groups (linear and simultaneous)
• Auto-attendants / IVR
• Multiple outbound number presentation
• For: 2–10 user offices that need to route callers intelligently

Anywhere, mobile-first with messaging

Everything in Office plus:

• WhatsApp Business integration (two-way)
• Two-way SMS
• eSIM handset integration
• For: mobile-heavy teams, customer-service-led businesses, field teams

We'll quote on your specific size and usage, 3CX-style per-SC pricing doesn't apply here; PhoneLine+ is simple per-user-per-month.

PhoneLine+ vs Horizon (also Gamma)

A question we get a lot:

	PhoneLine+	Horizon
Target	Micro and small businesses	SME to mid-market
Price point	Low per-user/month	Higher per-user/month
PBX features	Lean, hunt groups, IVR	Full PBX, queues, call recording, agent licensing
CRM integrations	Limited	Broader (Microsoft, HubSpot, Salesforce, etc.)
Reporting	Basic	Advanced
Hardware ecosystem	IP phones supported, not required	Full desk-phone deployments common

Rule of thumb: under ~10 users who don't need call recording or queues, PhoneLine+. Over that, Horizon or a managed 3CX. We can migrate either direction later if the business grows out of the tier.

PSTN switch-off deadline

BT announced the UK-wide retirement of the PSTN/analogue network. By January 2027, no new PSTN lines will be installed and existing analogue lines will be migrated. If you're still on a traditional BT business line, you'll need a replacement, PhoneLine+ is one of the most common landings for businesses that don't need a full PBX.

Moving earlier than the deadline is smart, it avoids the last-minute scramble and means you've had time to train staff and iron out any number-porting hiccups before the old line disappears.

What switching looks like with us

For PhoneLine+ deployments we typically handle:

• Number audit, identify all numbers to port, check they're portable (some old numbers need extra work)
• Licence selection, right tier per user, not just "everyone gets Anywhere"
• Pre-port parallel running, you're live on PhoneLine+ before we move the number across
• Number porting, usually 1–2 weeks with Gamma depending on the losing provider
• Device setup, IP phone delivery (if needed), app rollout, ATA for any legacy kit
• IVR / hunt-group design, simple call flow, documented, trained to the team
• Handover, admin access stays with you, but we're on hand for changes

Typical end-to-end: two to three weeks, zero downtime on cutover day because you run both old and new in parallel.

Want a quote for your specific numbers and user count? Get in touch.