How to Calculate What an Hour of Downtime Really Costs Your Business

If your systems went down for an hour tomorrow morning, what would it cost your business?
When asked this question, most Dutch business owners and IT managers pause. Then they give a number — usually a rough guess, and almost always too low.

This is not a careless oversight. It is a structural problem. The costs of IT downtime do not arrive on a single clean invoice. They scatter quietly across your working day: an invoice that cannot be sent, a client call that cannot be taken, a team of ten people sitting idle waiting for the server to come back online, a prospective customer who tried to reach you at exactly the wrong moment and did not try again.

According to research by Computable, the average ICT incident costs a Dutch business €82,838 — made up of roughly €58,400 in operational disruption and a further €24,438 in recovery costs. For MKB businesses specifically, Dutch market research puts the average loss at €1,500 per hour of IT downtime. The actual number for your business may be higher. The point is: you should know your number, not guess it.

This blog walks you through a straightforward four-step calculation you can complete in under ten minutes. No complicated spreadsheet. No consultancy required. Just a clear method for putting a real figure on a risk that most businesses quietly underestimate.

Start with the most direct cost: the revenue your business cannot generate while systems are unavailable.

The figure of 2,080 represents the approximate number of working hours in a Dutch business year (52 weeks × 40 hours). If your business runs fewer hours or has seasonal peaks, adjust accordingly.
This is a conservative baseline. It assumes revenue loss is evenly distributed across all hours, which is rarely true. If your systems go down during your busiest period — end of quarter, a Monday morning, a product launch — the actual loss will be higher.

If your business delivers time-based services (legal, consulting, accounting, IT services), the revenue loss per hour is more direct: it is the billable time your team cannot log. For a 10-person consultancy with an average billing rate of €120 per hour and 70% utilisation, that is €840 per hour of lost billable capacity before you account for anything else.

Your number: €_______ in lost revenue per hour

While systems are down, your team is not sitting doing nothing — they are trying to work around the problem, waiting for updates, or simply unable to do the work they are paid for. All of that has a cost.

Tech issues are resolved before you hear about them. Problems are logged, triaged, and fixed through a defined support process. Your team knows where to go for help, and it is not your mobile number.

A few points worth noting:

• Not all employees are equally affected. A server outage may ground your finance team entirely while your warehouse staff carries on. Be specific about who actually cannot work when which systems fail.
• Employer costs in the Netherlands include social security contributions, pension contributions, and employer insurance — typically adding 25–35% on top of gross wages. The €47 per hour figure from CBS already accounts for this, making it a useful starting point.
• If your business has staff across multiple locations or departments, consider running this calculation per team and adding up.

Your number: €_______ in idle employee costs per hour

This is the component most people miss entirely, and it changes the number significantly.
When systems come back online after an outage, things do not simply resume where they left off. There is a recovery period: backlogged work to clear, data to re-enter, client communications to catch up on, and a team that spent the outage stressed and context-switching rather than focused on productive work.
A standard rule of thumb used in IT continuity planning is to add 50% to account for recovery overhead. A one-hour outage rarely costs just one hour — it costs approximately 1.5 hours of total disruption.

If your subtotal from Steps 1 and 2 was €2,000 per hour, your realistic downtime cost is €3,000 per outage event. Not because systems are down for 1.5 hours, but because the disruption extends beyond the outage window.For longer outages — multi-hour or multi-day — the recovery multiplier often increases. A four-hour outage may carry a recovery overhead of 100% or more, particularly if it involves data loss, client escalations, or manual workarounds that need to be unwound.

Your number: €_______ total cost per downtime event (subtotal × 1.5)

This is the most difficult component to assign a number to, and often the most significant over time.
Consider what happens on the client side during an outage. A customer calls to place an order and gets no response. A prospect visits your website to get in touch and hits a dead end. A client who relies on your portal to access documents finds it unavailable at a critical moment.
Some of those people wait. Many do not. And the ones who do not wait rarely send a note to tell you they are leaving.

Rather than trying to calculate an exact figure, ask yourself two questions:

• What is the average lifetime value of a client to your business? Even a conservative estimate — say €5,000 over two years — gives you a reference point.
• How many clients or prospects might have a critical interaction with your business during a one-hour outage? On a busy Tuesday morning, the answer might be three or four.

One lost client relationship at €5,000 lifetime value doubles the cost of an outage that otherwise came to €4,500 in revenue and staff costs. Two lost clients triple it.
This is not a hypothetical. Research on IT service disruptions consistently shows that customer churn following outages is both real and systematically underestimated — in part because it is invisible. Clients do not usually call to cancel. They simply stop coming back.

Here is a worked example based on a typical Dutch MKB business.

Now ask the question that follows: how many hours of downtime would it take to cost more than a full year of managed IT support? For this business, the answer is likely fewer than two incidents.

Running this calculation for the first time tends to produce a specific reaction: surprise at how large the number is, followed immediately by the realisation that the business has never thought about IT investment in these terms.
Most technology purchasing decisions in Dutch SMEs are made based on cost. How much does it cost per month? What is the cheapest option that covers our needs? These are reasonable questions. But they are incomplete without the denominator: how much does an outage cost, and how often do outages happen without proper infrastructure in place?

Dutch businesses are not outliers when it comes to outage frequency. Research from the Uptime Institute shows that 80% of organisations experienced at least one significant outage in the past three years. Network and connectivity issues account for 31% of all IT service outages. Hardware failure, software errors, and — increasingly — cybersecurity incidents make up most of the rest.
For MKB businesses in the Netherlands, the cybersecurity dimension is particularly relevant. Ransomware attacks on SMEs occur at more than double the rate of large enterprises, according to the 2025 Verizon Data Breach Incident Report. The average recovery time from a ransomware incident is 24 days — not 24 hours. Multiplied against even a modest hourly cost, the financial exposure becomes significant.

When businesses choose IT infrastructure or support based on minimum monthly cost, they are making an implicit bet: that outages will be infrequent and short. Sometimes that bet pays off. Often it does not. And when it does not, the reactive cost — emergency contractor fees, data recovery, extended downtime while the problem is diagnosed — typically far exceeds what proactive monitoring and managed IT support would have cost over the same period.
As one Dutch IT provider puts it: “Een uur downtime bij vijf medewerkers kost al snel meer dan een maand onderhoud.” (One hour of downtime with five employees costs more than a month of maintenance.) The maths tends to bear this out.

Knowing your downtime cost is only useful if it informs a decision. Here are the practical steps Dutch SMEs can take, broadly in order of priority:

Not all downtime is equal. An outage affecting your email is inconvenient; an outage affecting your payment processing or client portal is immediately costly. Map out which systems, if they failed, would produce the largest hourly loss. These are your highest-priority continuity investments.

Research from Dutch IT provider Daemen ICT indicates that proactive monitoring prevents approximately 90% of incidents that would otherwise cause an outage. The logic is straightforward: monitoring detects anomalies before they become failures. A server that is running at 97% disk capacity can be managed before it crashes; a server that crashes without warning costs hours to recover.
Managed IT service providers in the Netherlands typically include 24/7 monitoring as a standard component of their service. The question for most MKB businesses is not whether they can afford it, but whether they can afford the alternative.

A backup that has never been tested is not a backup; it is a hope. The difference between a two-hour recovery and a two-day recovery often comes down to whether backup restoration procedures have been rehearsed. Build a regular backup test into your IT maintenance calendar.

Even with excellent infrastructure, incidents happen. The businesses that minimise their downtime costs are the ones that can respond quickly and systematically when something goes wrong. An incident response plan does not need to be complex — it needs to be clear. Who gets called? What gets checked first? What do you communicate to clients, and when?

Your business changes. Revenue grows, team size changes, and your digital dependencies expand. The downtime cost you calculate today may understate the risk you face in two years. Make this an annual review item alongside your IT budget conversation.

Most Dutch business owners have never sat down and calculated their actual hourly downtime cost. The ones who do are rarely surprised by the direction of the answer — only by the size of it.
Running the four-step calculation in this blog takes under ten minutes. What it produces is not a theoretical risk figure; it is a practical reference point for every IT investment decision your business makes going forward. Managed IT services, proactive monitoring, backup and recovery infrastructure — all of them look different when viewed against a concrete downtime cost rather than a vague sense of risk.
The question worth asking is not “how much does IT support cost?” It is “how many hours of downtime would it take to cost more than what I spend preventing it?” For most Dutch MKB businesses, the answer is fewer than people expect.

If you have worked through the four steps in this blog, you now have a clearer picture of what downtime actually costs your business. The next question is whether your current IT infrastructure is built to minimise that risk — or whether it is quietly absorbing it.

No pressure. No jargon. Just a clear picture of your risk and what it would take to reduce it.