3CX vs 8x8: honest UK comparison for SMEs

What 8x8's X-series tiers actually deliver.

8x8 markets four tiers. For UK SMEs the meaningful choice is X2 versus X4 — the contact-centre tiers (X6, X8) only make sense for inbound-call-heavy operations with dedicated agent pools.

X2 — £22/user/mo. Voice + video + chat in one app, unlimited calling to 14 countries (UK landlines and mobiles included), basic queues, basic recording. Good for general SME use without contact-centre ambitions.
X4 — £32/user/mo. X2 plus supervisor analytics, advanced reporting, call quality monitoring, and the start of agent-management features. Worth the £10/user uplift if you have 10+ inbound reception/sales staff and a manager who looks at the numbers.
X6 — contact centre, ~£75/user/mo. Skills-based routing, omnichannel, WFM. SME-relevant only for inbound contact centres above 20 agents.
X8 — £110+/user/mo. Full contact centre. Enterprise positioning.

For most UK SMEs the realistic 8x8 choice is X2. X4 makes sense only if the reporting and supervisor features earn back the price uplift.

Pricing comparison — 25 users on the equivalent tier.

Line item	8x8 X2	3CX (Port Phones managed)
Per-user monthly fee	8x8£22 / user8x8.com UK list. Includes unlimited UK domestic calling.	Port PhonesQuotedAll-in (licence + hosting + SIP + support). See how we price.
Monthly (25 users)	8x8£550 / mo	Port PhonesQuoted
24-month difference	~£8,400£350/month differential, × 24 months.

Pricing comparison — 75 users.

At 75 users, X4 tier (£32/user) becomes common because the supervisor reporting becomes useful at this scale:

Line item	8x8 X4	3CX (Port Phones managed)
Monthly (75 users)	8x8£2,400 / mo75 × £32.	Port PhonesQuotedPRO 16 SC + UK hosting + Gamma SIP + support.
24-month difference	~£45,000£1,875/month differential, × 24.

8x8 UK pricing snapshot May 2026 from 8x8.com/uk/pricing. Managed 3CX is quoted per deal, see how we price.

Where 8x8 wins.

Integrated voice + video + chat in one app. 8x8 Work bundles all three into a single user experience. 3CX has video and chat too (on PRO) but the app is more "PBX with extra features bolted on" than "unified communications first".
Unlimited UK calling included in the per-user price. No per-minute charges to track. With 3CX you pay SIP minutes through your partner (typically £0.005–0.01 to UK landlines/mobiles); for heavy outbound callers (100+ minutes/user/day) this adds up. For typical SME usage (~30 minutes/user/day) the variable cost is trivial vs the £14/user saving.
Internal contact-centre upgrade path. Moving from X2 to X4 to X6 is a tier change inside 8x8. Scaling 3CX into a real contact centre means moving to AI tier or adding third-party contact-centre overlay. 8x8's growth path is cleaner if you know contact centre is coming.
Mobile app + desktop client polish. 8x8's apps are well-designed and consistent across platforms. 3CX's apps are functional and continuously improving but less unified.

Where 3CX wins.

Per-system pricing. 75 users on X4 costs £2,400/month. 75 users on 3CX-managed costs £525/month. Adding 10 more users to X4 costs £320/month extra forever. Adding 10 more users to 3CX-managed costs handsets and admin time once.
Recording without tier upgrade. 3CX PRO includes call recording with retention policy controls. 8x8 X2 includes basic recording; X4 adds more controls. Different feature gating — typically a wash, occasionally a 3CX win at PRO tier vs the equivalent 8x8 X4 cost.
UK partner relationship. 3CX through a UK partner gives you one named UK contact. 8x8 UK support is a global queue inside an American company. Reputable in both cases; one is a relationship.
UK data residency by default. 3CX through a UK partner with UK hosting keeps recordings on UK soil. 8x8 data residency configurable for UK customers, but ask before signing if regulated data matters.

The break-even calculation.

Where does the price differential get small enough that 8x8's UX wins on net? Rough numbers:

Under 10 users: 8x8 X2 at £22 per user puts a ten-person office at £220/mo. Managed 3CX at the smallest capacity band lands in a similar place, so pick on how the two feel to use rather than on price. How we price.
10–30 users: 3CX-managed has a £200–500/month advantage. Real money but maybe not switching-cost-justifying if you genuinely prefer 8x8's UX.
30+ users: The differential compounds. At 50+ users, the 24-month TCO gap is £20k+. Most firms switch.
Contact-centre-leaning 30+ agent inbound: X6 may genuinely be the right product for that workload. 3CX AI tier is capable but not a peer.

3CX vs 8x8: the per-seat maths, done honestly.