Why this decision matters now
Avaya filed for Chapter 11 in 2017 and again in 2023. The company emerged each time, but the strategic direction is now unambiguous: enterprise contact-center is the future, and on-premises SMB telephony is being managed for the wind-down. Avaya's official position is that IP Office stays supported on an extended schedule; the reseller community's read is that pricing, parts availability, and feature investment are all degrading. If you bought an IP Office 500v2 in 2014, you're now running a system that's two ownership changes and two bankruptcies past its design window.
None of that means your phones will stop working tomorrow. They probably won't stop working in 2027. But every quarter you stay on the platform, three things get harder: finding a tech who knows it, finding spare parts at a sane price, and getting the next quote on what to do about it. The longer you wait, the more leverage your vendor has.
Path 1 — Stay on Avaya, renew support
The "do nothing yet" path
This is a legitimate strategic choice if you have a known end-date. If you're selling the business in 18 months or moving offices in a year, paying for one more support cycle and replacing later avoids paying twice. Renewal pricing is also softening as Avaya competes against itself (selling ACO to its own customer base), so 2026 renewal quotes often come in 10–20% under 2024 levels.
The trap: this is most often chosen by accident, not by plan. You miss the renewal-decision window, your reseller auto-renews you, and three years later you're paying $6,000 a year to keep a system alive that costs $228 per user per year to replace with cloud. Set a calendar reminder for 90 days before contract expiry and treat that as your real decision point.
Path 2 — Full cutover to a cloud VoIP
The "rip and replace" path
This is the path roughly 70% of Avaya SMBs end up choosing. The numbers are hard to argue with: cloud removes the PBX hardware, the support contract, the maintenance window scheduling, and the "what if it dies on a Friday" stress, all for less than the annual support contract used to cost.
The actual move is more boring than the Avaya horror stories suggest. The cloud vendor handles number porting, configures the dial plan to mirror what your staff is already used to, and runs the new system in parallel with the old one for 7–14 days. Nobody dials a new number on cutover day; the IP phones get a new config push and the old PBX gets unplugged.
The non-obvious cost item: desk phones. If you have Avaya J139s or J169s, they can usually be flashed to SIP firmware and registered to the cloud — that's free. If you have Avaya 9608, 9611, or 9621 (H.323 phones), they can be flashed but it's finicky and a competent shop charges $25–$40 per phone for the conversion. Digital and analog phones (94xx series, 6400-series digital) must be replaced. Budget $99–$229 per phone for replacements if needed; you can also stay app-only on iPhone/Android and skip the deskphone refresh entirely.
Path 3 — Hybrid (Avaya core + cloud branches)
The "incremental" path
If you're opening a fifth location and the thought of putting a small IP Office 500 there gives you indigestion, hybrid is exactly the right answer. You drop a cloud VoIP at the new branch, link it to the HQ Avaya via SIP trunk so extension dialing still works across all locations, and you've avoided buying a sixth-generation PBX you'll regret in three years.
The trick that makes hybrid work: consistent extension ranges and a uniform dial plan. If HQ uses 200–399 for staff extensions, the new cloud branch gets 400–599, and the SIP trunk between them routes any 5xx-dialed call from HQ to the cloud branch transparently. Users at HQ keep dialing their five-digit extensions; the new branch is just "another wing." When you're ready to move HQ off Avaya later (Path 2), you do it during a planned weekend without changing how anyone dials.
The thing that kills hybrid setups: too many vendors with too little coordination. The cloud VoIP, the SIP trunk provider, and the Avaya reseller need to talk to each other at least once. If they don't, you'll spend three weeks tracking down why HQ-to-branch transfers drop after 30 seconds. Insist on a kickoff call with all three before the first port date.
Path 4 — Avaya Cloud Office (ACO)
The "vendor-recommended" path
ACO is Avaya's official cloud product and the path your existing Avaya reseller will quote you first. It's worth understanding what you're actually buying: ACO is RingCentral under the hood, white-labeled for Avaya. The infrastructure, codecs, mobile apps, and admin portal are all RingCentral; the branding and the support contract are Avaya.
This is fine if you value continuity with your reseller. But the implications are worth thinking through: you're now in two contractual relationships (Avaya the brand, RingCentral the carrier), the pricing tracks RingCentral's, and feature releases follow RingCentral's roadmap on a slight delay. If you'd consider going direct to RingCentral, the pricing is usually marginally better there for the same product. If you'd consider any other cloud VoIP (Nextiva, voip.army, 8x8), ACO is competing on brand familiarity, not on technical merit.
Where ACO does win: existing Avaya contact-center integrations. If you run Avaya Aura Call Center Elite or Workforce Optimization, ACO has direct integration that other clouds don't. For pure SMB voice (no contact center), there's no technical advantage worth a premium.
Path 5 — SIP trunk overlay (replace trunks, keep PBX)
The "buy time" path
This is the path nobody talks about because it doesn't sell new phones. You keep the Avaya PBX, you keep all your phones, and you just replace the carrier side: pull the T1/PRI lines, drop in SIP trunks pointed at your Avaya's external SIP interface. Your monthly trunk bill drops 40–70% overnight, your dialtone gets noticeably cleaner, and you've bought yourself another 2–4 years of runway on the Avaya at low cost.
This is the right answer when: your Avaya is healthy and well-maintained, your staff knows it, the only pain point is the rising AT&T or Spectrum trunk bill, and you're not ready to retrain the office on a new system this year. The longer-term trap is that Path 5 is so cheap to set up that businesses stay on it for a decade and miss every opportunity to modernize.
Technical note: not every Avaya version supports SIP trunks gracefully. IP Office releases 9 and later (most installs from 2014+) handle it fine. Older IP Office 8.x and Definity G3 need additional hardware (a Session Border Controller or a SIP gateway like an AudioCodes Mediant). Get a competent shop to scope it; an unprovisioned PBX will pass calls but mangle features like distinctive ring and DTMF on transfers.
Which path fits your business
| Your situation | Likely best path |
|---|---|
| 1–25 users, single site, Avaya is > 8 years old | Path 2 (cloud cutover) |
| 25–100 users, single site, Avaya works but T1 bill hurts | Path 5 (SIP overlay), revisit in 18 months |
| Multi-site, HQ Avaya healthy, opening new branches | Path 3 (hybrid) |
| You run Avaya Aura with Call Center Elite | Path 4 (ACO) or stay until contact center plan is clear |
| Planning to sell business / merge / relocate within 12 months | Path 1 (renew, decide later) |
| Avaya hardware is failing and you need a fix this month | Path 2 (cloud cutover, can stand up in 1 week) |
| Heavy compliance recording requirement (legal, healthcare) | Path 2 or Path 3 with a vendor whose recordings meet your retention rule |
Five mistakes that cost real money
1. Buying new Avaya phones in 2026. If your reseller is quoting J189s for a fleet refresh, stop. Those phones list at $300+ each and lock you into the Avaya path. The same money on Yealink T46U or Poly VVX450 (both standard SIP) buys you future portability across any cloud provider.
2. Porting numbers before the cutover is configured. Number ports are not reversible quickly. Port first, cutover second, and your inbound calls get black-holed for a day. The right order is: stand up new system parallel to old, test thoroughly, then submit port request with new system as the target. The old PBX accepts inbound calls right up until the port completes.
3. Forgetting the analog stuff. Fax machines, alarm panels, door buzzers, gate intercoms, postage meters, elevator phones, paging systems — these are all on FXS ports of the Avaya. The new VoIP needs an analog adapter (ATA) at the site to keep them working, or you swap them for IP-native devices. Make a list before cutover day, not after.
4. Skipping the dial plan documentation. The Avaya in your closet has 11 years of accumulated tweaks: this DID rings to that hunt group; this extension forwards to that cell after 3 rings; this auto-attendant sends Spanish-language callers to extension 405. Get the current behavior into a spreadsheet before you migrate, or you'll spend three weeks chasing "but it used to do X" tickets.
5. Underestimating training. Your front desk receptionist has used the same Avaya for 8 years. The new system's call park, transfer, and intercom are slightly different. Budget two hours of training per "power user" (anyone who handles > 30 calls a day) and a quick-reference cheat sheet for everyone else. Skipping this is how you get "the new phones are terrible" feedback that was actually "I don't know which button does transfer-to-voicemail."
FAQ
Is Avaya going out of business?
Not in the sense of closing. Avaya emerged from its second Chapter 11 in 2023 as a private company and continues to operate, focused primarily on enterprise contact-center and on its Avaya Cloud Office partnership (ACO, powered by RingCentral). On-premises IP Office and Aura remain supported but new SMB sales have shifted to ACO. Most resellers treat the on-prem lines as "maintain, don't expand."
Can I keep my Avaya phones after migrating?
Sometimes. Avaya J100 series (J139, J169, J179, J189) are standard SIP and can usually be reflashed to register with most cloud VoIP providers. Older 96x1 phones (H.323) can be flashed to SIP firmware but the process is finicky. Digital phones (95xx series and analog desksets) cannot move — they need replacement.
How long does an Avaya migration take?
Small (1–25 users, single site): 1–2 weeks elapsed, ~10 hours of actual work. Mid-size (25–100 users, 1–3 sites): 3–4 weeks, ~40 hours. Multi-site (100+ users, 4+ locations): 4–8 weeks, ~80–160 hours. The long pole is almost always number porting, not equipment.
What's the cheapest way to move off Avaya?
Path 5 (SIP overlay) is cheapest upfront — $150–$300 setup, $15–$25 per channel monthly — because you keep your existing PBX. But it's the most expensive long-term, because you keep paying for PBX support and the inevitable next migration. Cheapest long-term is Path 2 (cloud cutover) at $19–$49 per user with no setup fees.
Will my call recordings transfer to a new VoIP system?
No — existing recordings live in the Avaya recorder's storage (Witness, NICE, Verint, or Avaya ACR). Options are: (1) export to long-term archive before decommissioning, (2) keep the recorder as a read-only archive, (3) skip historical recordings and start fresh. For compliance retention, option 1 is usually required.
Related reading on voip.army
- Replace Avaya — free migration, no contract
- All legacy PBX migrations — Nortel, Toshiba, Mitel, NEC, Comdial, Panasonic, Samsung, ESI, Allworx
- Supported VoIP phones — what works on voip.army
- Cloud VoIP comparisons — vs RingCentral, Nextiva, Vonage, 8x8, more
Disclaimer: This guide is general guidance, not a replacement for vendor-specific quotes. Talk to two or three providers before signing — the gap between best and worst pricing on the same project is routinely 30–50%.