Internet Downtime Impact Calculator
Calculate the true cost of internet outages to your business - including lost productivity, revenue impact, and whether investing in redundancy pays for itself.
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Average Internet Downtime Costs by Business Size
| Business Size | Employees | Cost per Hour | Annual Cost (no redundancy) | Recommended Solution |
|---|---|---|---|---|
| Micro | 1–5 | £200–£500 | £4,000–£10,000 | 4G/5G backup |
| Small | 6–25 | £500–£3,000 | £10,000–£60,000 | Dual ISP or 4G failover |
| Medium | 26–50 | £2,000–£8,000 | £40,000–£160,000 | Dual ISP + leased line |
| Large SME | 51–100 | £5,000–£15,000 | £100,000–£300,000 | Leased line + FTTP backup |
| Enterprise | 100+ | £10,000+ | £200,000+ | Dual leased lines + SD-WAN |
Costs based on UK SME averages assuming £150,000 revenue per employee, 85% staff affected, and 5 incidents of 4 hours per year. Actual costs vary by industry and internet dependency. Talk to Cloudswitched about resilient connectivity.
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Frequently asked questions
The true cost varies widely, but most UK SMEs lose somewhere between £100 and £1,000+ per hour of internet downtime once you account for idle staff time, lost sales, and missed customer response. Businesses reliant on cloud phone systems or e-commerce typically sit at the higher end of that range.
For most UK SMEs, a low-cost 4G/5G backup connection (typically £20-£50/month) pays for itself after avoiding just one or two hours of downtime a year, especially if you rely on VoIP or cloud applications. This calculator compares the annual cost of redundancy against your calculated downtime cost to show the payback point.
Reliability varies by provider and connection type, but most UK SMEs on standard broadband experience some unplanned downtime a few times a year, while leased lines with SLAs typically guarantee 99.9%+ uptime with compensation clauses for breaches. Redundancy planning matters most for businesses without an SLA-backed connection.
A 99.9% SLA allows roughly 8.7 hours of downtime per year, while 99.95% allows around 4.4 hours and 99.99% allows just under an hour. Leased lines commonly offer 99.9%-99.99% SLAs with service credits if breached, whereas standard broadband typically comes with a best-efforts service and no formal uptime guarantee.
