Client Concentration Risk Calculator
How much of your income depends on one client. Enter what each client paid you and see whether losing your biggest would be a setback — or a crisis.
Your details
Rough figures are fine — you can refine later.
How we calculate this
We measure how much of your income depends on one client.
1. Total revenue. The sum of what every client paid you.
2. Top-client share. Your largest client’s revenue ÷ total revenue.
3. Risk level. At or above 50% we flag high risk (a single point of failure); 30–50% is moderate; below 30% is comparatively diversified. The 50% boundary counts as high.
This is a risk-awareness tool, not financial advice. It’s a snapshot of one year — a client that’s big now may shrink, and vice versa.
Primary sources
- Revenue concentration / single-customer dependency risk analysis (small-business finance)
One client shouldn’t be able to end your business
Freelancers love a big anchor client — steady work, a reliable deposit, a relationship that just works. The hidden danger is dependence. If a single client is half your income and they cut budget, bring the work in-house, or simply go quiet, you don’t lose a client — you lose half your business overnight, with no notice.
This calculator measures that exposure. Enter what each client paid you over the last year, and it shows the share riding on your biggest one, plus a plain-English read on whether that’s a healthy spread or a single point of failure.
How to read your number
Below 30% — comparatively diversified. No single client can sink you, which is exactly where you want to be. Keep new work flowing so it stays that way.
30% to 50% — moderate. It’s manageable, but one client at a third or more of your revenue deserves attention. Grow your other clients so the concentration falls over time.
50% or more — high risk. One client effectively decides whether you make rent. This isn’t a someday problem to fix; it’s the most important thing your business can work on, because the downside is sudden and severe.
A common resilience target is no client above roughly 25% of revenue. That way, losing any single client is a bump you can absorb, not a cliff.
Why concentration sneaks up on you
Concentration rarely feels risky in the moment. A great client gives you more work, you happily take it, and because they’re easy and lucrative you stop chasing new leads. Slowly, they become most of your income — and the busier they keep you, the less time you spend building the pipeline that would protect you if they left.
The fix is to treat marketing as ongoing infrastructure, not something you do only when work dries up. Turn one-off buyers into repeat clients, productize a service so you can serve more people with less custom effort, and keep a trickle of outreach going even in your busiest months.
Where it connects
This tool pairs with the runway calculator — if your concentration is high, a longer cash runway is your safety net — and with income smoothing, which helps you bank the good months a big client provides so a sudden loss isn’t an immediate crisis.
What this is
A risk-awareness snapshot, not financial advice. It reflects one year of revenue; a client that dominates today may shrink tomorrow, and vice versa. Use it to decide where your business-development energy should go next.
Common questions
What is client concentration risk? + −
It’s the danger that comes from earning too much of your income from one client. If a single client is half your revenue and they leave, cut budget, or pay late, you face a sudden 50% income drop with little warning. Concentration risk measures how exposed you are to that single point of failure.
What percentage from one client is too much? + −
A widely used rule of thumb: no single client should exceed about 25% of your revenue. At 30% or more you’re in moderate-risk territory; at 50% or more, one client effectively controls whether you make rent. These aren’t hard laws, but they’re useful lines to manage against.
How do I reduce client concentration? + −
Grow the rest of your book: dedicate time to marketing and outreach even when you’re busy, turn one-off buyers into repeat clients, and productize services so you can serve more clients with less custom work. The goal is a pipeline where losing any one client is a bump, not a cliff.
Is a big anchor client always bad? + −
No — a large, reliable client can be a great foundation. The risk isn’t their size, it’s your dependence. Enjoy the anchor, but use the stability it provides to build other income so that if it ever ends, your business doesn’t end with it.
Keep going
Prepared for tax year 2026. Every rate and cap on this page cites a primary IRS or SSA source. Estimates only — not tax or financial advice. — for planning purposes only, not tax, legal, or financial advice.