The honest maths
Bandwidth is arithmetic, not mystery. Rough per-person concurrent load: general cloud work and email ~2–5 Mbps; HD video calls ~3–5 Mbps each; VoIP a mere ~0.1 Mbps per call (quality needs stability, not size); big file work and backups are the real consumers. So a 10-person office on cloud apps with a few video calls lives comfortably on 100 Mbps full fibre; a 30-person firm with heavy video and cloud storage wants 300–500 Mbps; and the moment large uploads matter — media, CAD, backups offsite — the question flips from download to upload, where FTTC's feeble up-speed embarrasses and full fibre or a leased line earns its keep.
What matters more than the headline number
Three things beat raw speed: upload symmetry (cloud-era work is two-way; 'up to 80 down, 20 up' is a 2015 answer); contention and consistency (a dedicated line's guaranteed 200 beats a shared line's theoretical 900 at 2pm); and resilience — for any business that stops when the internet stops, failover is worth more than another 100 Mbps. Our sizing conversation asks what you do, not what you'll pay — and quite often the honest answer is a cheaper service than you expected, configured properly. Check the sums against your bill with the calculator.
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Frequently asked questions
Is 'up to 80 Mbps' FTTC enough for a small office?
For 3–5 light users, often yes — but the ~20 Mbps upload bites the moment cloud backup or video matters. Full fibre usually costs similar now; we'll check your address.
When does a leased line become worth it?
When the internet is production-critical: many staff in cloud systems, uploads that matter, VoIP at scale, or an SLA your operations genuinely need. Our guide: it's a business-continuity decision, not a speed vanity one.
Do more staff always mean more bandwidth?
Concurrency matters more than headcount — 30 people lightly browsing use less than 5 people video-calling while syncing. We size on workload, which is why we ask.