Network Firewall Service Break-Even: About $215K/Month

Fixed costs $33.5K/mo Base overhead

Contribution margin 67% After direct spend

Break-even revenue $50.0K/mo Monthly target

Break-even timing Month 19 Cash break-even

Break-even calculator

Use this calculator to test monthly revenue, variable expenses, and fixed monthly costs against break-even for a network firewall installation service.

Lean Base Full

Monthly revenue Revenue is the top line that has to cover variable costs and overhead. $ Low sales High sales Variable expenses These are the direct costs that rise as installs and managed work grow. $ Lean costs Heavy costs

Money available to cover fixed costs $328,621 $450,167 revenue - $121,546 variable expenses

Margin ratio

73%

Covers fixed costs

Yes

Fixed monthly costs This is the monthly overhead the service must cover before profit starts. $ Light overhead Heavy overhead

Break-even chart Revenue Total costs

Which expenses stay fixed and which move with sales for this firewall service?

Cost classification

Break-even is only reliable when direct service spend is split from committed overhead. Revenue-linked items reduce contribution margin, while rent, insurance, SOC upkeep, and staffed capacity set the monthly hurdle.

Expense	Cost	Break-Even Treatment	Common Mistake
Software Licensing and Tools	Variable	Apply as a revenue-linked service delivery load: 12.0% in the first year and 10.5% in Year 2.	Treating licenses as flat overhead when usage rises with client volume.
Hardware and Equipment Costs	Variable	Deduct from revenue before contribution margin: 8.0% in the first year and 7.5% in Year 2.	Ignoring hardware drag in early jobs and overstating gross margin.
Sales Commissions and Bonuses	Variable	Model as sales-volume spend: 8.0% of revenue in the first year.	Putting commissions below break-even and hiding true acquisition pressure.
Third-Party Contractor Services	Variable	Include as direct fulfillment support: 5.0% of revenue in the first year.	Assuming all delivery work is handled by payroll staff.
Office Rent and Utilities	Fixed	Carry as $12,000 per month from Month 1 through Month 60.	Spreading rent across jobs instead of treating it as the monthly floor.
Insurance Premiums	Fixed	Carry as $3,500 per month from Month 1 through Month 60.	Leaving insurance out of break-even because it is not tied to installs.
SOC Infrastructure Maintenance	Fixed	Carry as $5,500 per month from Month 1 through Month 60.	Moving it with revenue when the operating commitment is already in place.
Customer Success Manager and Operations Manager payroll	Semi-fixed	Add as capacity steps starting in Year 2 when those roles begin.	Treating salaried staff as per-job labor when payroll is committed.

How does break-even shift from lean to full service in a network firewall installation business?

Scenario table

Lean work barely carries the overhead, but the base and fuller stacks lift contribution margin and spread fixed payroll and marketing across more revenue. That’s what moves the break-even line, not just top-line growth.

Planning cases only; actual break-even will move with win rate, staffing mix, and contractor use.

Scenario	Monthly Revenue	Variable Costs	Fixed Costs	CM Ratio	Operating Profit	Break-Even Signal
Lean firewall management	$1,027K	$339K	$1,102K	67%	$-414K	Needs about $1,645K/month to break even, so this case stays under pressure.
Base mixed-service stack	$2,498K	$749K	$1,506K	70%	$243K	About $2,151K/month break-even gives this case a small cushion.
Full recurring support stack	$4,502K	$1,216K	$2,027K	73%	$1,259K	About $2,777K/month break-even leaves the widest cushion if utilization holds.

What breaks the break-even plan for this network firewall installation service?

Stress test

The first pressure point is slower client acquisition, because a 15% revenue drop almost wipes out the cushion. A 10% lift in fixed overhead or a 5-point margin drop still leaves room, but both together push the model into a clear gap.

Stress Case	Changed Assumption	Break-Even Revenue	Revenue Gap	Risk Signal
Current plan	No change.	$2.15M	$243K cushion	The plan clears break-even, but the buffer is not large.
Revenue shortfall	Revenue falls 15% from plan.	$2.15M	$19K gap	Slower client acquisition almost erases the cushion.
Fixed-cost pressure	Fixed overhead rises 10%.	$2.37M	$93K cushion	Rent, staffing, or support creep cuts the buffer fast.
Margin pressure	Contribution margin falls 5 points to 65%.	$2.32M	$118K cushion	Higher subcontractor labor or vendor fees hit margin first.
Combined pressure	Revenue falls 15%, fixed overhead rises 10%, and margin falls to 65%.	$2.55M	$276K gap	Slower sales and cost creep push the plan underwater.

What should the founder verify before signing the lease, hires, and launch spend?

Founder checklist

Don’t lock in the lease, the full Year 1 payroll, or the launch spend until you have booked install work and CAC near $1,250. Break-even is plausible, but only if pipeline, quotes, and cash all hold through the Month 18 low point.

1Pipeline ProofBooked installs

Get signed install work in hand before the lease or the $150K Year 1 marketing budget, and keep early CAC near $1,250.

2Overhead Load$33.5K/mo

Do not sign the $12K/month lease until the monthly fixed load of $33.5K, including rent, insurance, legal, telecom, supplies, training, travel, and SOC maintenance, sits inside booked revenue.

3Quote Margin67% CM

Test quotes on basic firewall management, advanced threat monitoring, compliance security, and incident response work, because the Year 1 mix only supports break-even if contribution stays near 67% after software, hardware, commissions, and contractors.

4Staff Ramp7.0 FTE

Prove the first-year workload can keep the 7.0 FTE plan busy before you add the Month 13 support and admin hires and the Month 25 marketing role.

5Cash Floor-$431K

Set cash aside for the Month 18 low point, since the model does not reach breakeven until Month 19 and the drawdown peaks at about $431K.

6Launch Capex$615K

Delay noncritical launch spend until recurring demand is visible, because the opening capex stack totals $615K and can trap cash before support revenue stabilizes.