What should replace your old Avaya phones? A field guide for 2026

If you've decided your Avaya estate has run its course, the next question is: replace it with what? This is a plain guide to the three broad routes UK SMEs actually take in 2026, with honest pros and cons for each. No affiliate links, no vendor cheerleading.

The three routes

Roughly:

1. Move phone calls into your Microsoft 365 stack (Teams Phone). Best for firms already deep in M365.
2. Zoom Phone. Best for firms already all-in on Zoom for meetings.
3. Dedicated SIP handsets on a hosted UC platform. Best for firms who want desk phones on the desk, not just soft phones on laptops.

Most SMEs land somewhere on the spectrum. Some hybrid these routes — hosted UC for most people, a few desk phones for reception. That's fine.

Route 1 — Microsoft Teams Phone

What it is. Voice calling built into the Teams app you're already using. Calls hit the same client on the same laptop / phone / dedicated handset your users already have.

Best for.

• Firms already on Microsoft 365 Business Standard or Business Premium.
• Users happy to make calls from a headset on their laptop rather than a physical desk phone.
• Businesses with users spread across offices and home working.

What you need.

• Microsoft Teams Phone add-on licence per user (about £6 per user per month at time of writing — don't quote that as gospel).
• A "calling plan" or SIP trunk for outbound calls. Direct Routing (bring-your-own trunk) works out cheaper at volume; Calling Plans are simpler.
• Optionally: dedicated Teams-certified handsets on reception or shared desks.

Pros.

• One tool. Users don't have to learn a new client.
• Powerful presence and directory integration.
• Handles video, chat, screen-share, all in the same place.

Cons.

• Requires stable internet. No LAN-only fallback.
• Cost per user adds up on large estates.
• Microsoft-native admin tooling. If your existing IT support is heavily Google Workspace-shaped, there's a learning curve.

Teams-certified handsets to know: Poly Edge E series, Yealink MP-series (MP54, MP58), AudioCodes RX-series. All around 150-350 pounds per unit refurb / new.

Route 2 — Zoom Phone

What it is. Voice calling on Zoom's platform. Same client as your Zoom meetings, extended to phone traffic.

Best for.

• Firms already using Zoom heavily and unwilling to consolidate to Teams.
• Contact-centre-lite use cases where Zoom's queue management works well.

What you need.

• Zoom Phone licence per user.
• A calling plan (metered or unlimited) or a bring-your-own SIP trunk (Zoom calls it "Zoom Phone BYOC").
• Optionally: Zoom-certified handsets.

Pros.

• Very simple admin console.
• Strong meeting-to-call transitions.
• Fair pricing at small scale.

Cons.

• Ecosystem is narrower than Microsoft's.
• Zoom-centric — if you're moving off Zoom for meetings in future, you migrate again.

Zoom-certified handsets: Poly, Yealink, Grandstream — the same core suppliers as Teams but different firmware SKUs.

Route 3 — Dedicated SIP handsets on a hosted UC platform

What it is. Physical desk phones plugged into an internet connection, registered against a hosted phone platform (RingCentral, 8x8, Vonage Business, GoTo Connect, Nextiva, Webex Calling, or many others). No PC required to make a call.

Best for.

• Reception desks and shared spaces where a physical phone is the right form factor.
• Businesses whose users hate wearing headsets.
• Sites where you want desk phones as a fallback if the PC is off.

What you need.

• A hosted UC subscription. Prices vary widely, plans typically £8-£25 per user per month depending on features and provider.
• SIP handsets: Yealink T5x, Poly Edge, Grandstream GRP series, Cisco 88xx (used in some hosted deployments). Refurbished SIP handsets from £30-£100 per unit.
• A decent network connection with QoS if you're running many concurrent calls.

Pros.

• Familiar desk-phone experience.
• Physical handset survives a laptop reboot.
• Refurbished handsets are readily available and cheap.

Cons.

• Two devices to manage per user (phone + PC).
• Networking hygiene matters more (QoS, VLAN, PoE).
• More moving parts than a pure-software solution.

Handset rankings for 2026 SIP deployments

If you've decided you want physical desk phones and you're specifying models, the current secondary-market picture:

Solid entry choice: Yealink T33G / T43U / T46U. Colour screen, gigabit, works with most hosted platforms out of the box. Refurb pricing keeps them affordable. Yealink is the volume leader in UK SME SIP.

Solid mid-range: Poly Edge E320 / E450. Cleaner build than the Yealink, good handset ergonomics, well-supported on Teams-certified deployments.

Solid enterprise-tier: Cisco 8845 / 8865. Higher build quality, well-supported, but pricier and often requires a Cisco-certified admin.

Solid budget: Grandstream GRP2612 / GRP2614. Good value at the entry end. Firmware not as polished as Yealink but perfectly workable.

Avaya J-series as a reuse option. If you've already got J169, J179 or J189 handsets sitting in a stock cupboard, they can be re-provisioned against many hosted UC platforms with Avaya's SIP firmware (the SIG=SIP conversion documented by Avaya). Not always plug-and-play but doable. Worth checking before you buy new.

Match by business shape

• Solicitors, accountants, small consultancies (5-40 users). Teams Phone + a couple of Poly desk phones on reception. Simple. Cheap. Familiar tool.
• Manufacturing SME (20-60 users). Hosted UC with Yealink desk phones on the shop floor. Users on the office side get Teams softphone. Physical handsets where they need to survive rough conditions.
• Independent hotel (10-30 rooms). Specialist migration. Wake-up call, PMS integration and cost management make this a "get advice specific to your PMS" job, not a generic recommendation.
• Multi-site SME with poor rural broadband. Hybrid: on-prem PBX at the reliable-connection site, hosted UC everywhere else. Some Avaya IP Office estates end up in exactly this shape for another 3-4 years.

About your old handsets

Once you've picked your replacement, the old kit still needs to go somewhere. Some SIP handsets from your old estate can be reprovisioned. Digital Avaya handsets that only work with an Avaya PBX cannot come with you.

We collect old desk phones, wipe them properly, and issue a Certificate of Sanitisation. See What we buy — desk phones or drop us a note through the contact page.

See also: The PSTN switch-off explained · What to do with old Avaya digital phones in 2026 · Are old Avaya phones still useful in 2026?