Free Tool

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.

Enter Your Details

UK average is approximately £150,000 per employee per year
Average duration of each internet outage
UK SMEs average 3–8 internet outages per year without redundancy
What percentage of your staff cannot work without internet (typically 80–100%)

Average Internet Downtime Costs by Business Size

Business SizeEmployeesCost per HourAnnual Cost (no redundancy)Recommended Solution
Micro1–5£200–£500£4,000–£10,0004G/5G backup
Small6–25£500–£3,000£10,000–£60,000Dual ISP or 4G failover
Medium26–50£2,000–£8,000£40,000–£160,000Dual ISP + leased line
Large SME51–100£5,000–£15,000£100,000–£300,000Leased line + FTTP backup
Enterprise100+£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.

More Free Tools

Try our other free IT calculators and planning tools.

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.

Technology Stack

Powered by industry-leading technologies including SolarWinds, Cloudflare, BitDefender, AWS, Microsoft Azure, and Cisco Meraki to deliver secure, scalable, and reliable IT solutions.

SolarWinds
Cloudflare
BitDefender
AWS
Hono
Opus
Office 365
Microsoft
Cisco Meraki
Microsoft Azure

Latest Articles

18
  • Cloud Backup

Backup Retention Policy: A UK Business Guide to How Long You Should Actually Keep Your Data in 2026

18 Sep, 2026

A backup retention policy is the answer to a question most UK businesses have never actually been asked: how far back do you need to be able to go? In the...

Read more
17
  • Cloud Networking

Multi-Site Network Design: A UK Business Guide to Connecting Branch Offices to the Cloud in 2026

17 Sep, 2026

Multi-site network design is the decision most UK businesses make by accident. The second office gets a site-to-site VPN back to head office because that is...

Read more
16
  • Azure Cloud

Azure Cost Management: A UK Business Guide to Preventing Cloud Bill Shock in 2026

16 Sep, 2026

Azure cost management is the discipline that stands between a UK business and the invoice nobody expected. The uncomfortable part is that the invoice is almost...

Read more

Enquiry Received!

Thank you for getting in touch. A member of our team will review your enquiry and get back to you within 24 hours.