Sixty percent of your revenue can vanish in one email. It says "we are pausing all hiring," it arrives at 9:04 on a Tuesday, and it is read by 9:06. Half a year of income gone before lunch, and you would still have called them your best client that morning.
Tech recruiting lived this at scale in 2023. The firms that nearly died were rarely the weak ones. They were the ones whose biggest client had quietly become their employer.
That is what makes it dangerous. A dominant client means recurring reqs, easy communication, predictable invoices. Every incentive says lean in. But past a threshold you have not diversified a business, you have acquired a boss with extra steps, and they hold leverage over your fees, your terms and your calendar whether they use it or not.
Cross a line and the response is never to serve the anchor client less. Serve them brilliantly. The fix is adding logos underneath them, which is a business development cadence question, and it has to happen while things are good. Diversifying after the freeze email is twice as hard with half the runway.
If one client is over 40 percent today, treat it as the house being on fire politely. Run a 90 day sprint: revival emails to every past client in month one, an outbound push into the anchor's peer companies in months two and three, using your delivery for the anchor as the proof story. You already fill these roles at this scale. Saying so to the anchor's ten nearest competitors is the fastest safe pipeline you can build.
Concentration should also shape terms. The anchor client asking for a fee cut holds more leverage over a 60 percent supplier than a 25 percent one, and they know it even if it is never said. Every point of diversification is negotiating power you did not have last quarter. Owners who track one number a month should track this one.
A common working rule is no client above 30 percent of revenue and the top three below 60 percent combined. Above that, a single hiring freeze or contact change can create an existential quarter.
Keep serving the anchor at full quality while running a deliberate acquisition sprint underneath it: reactivate past clients, then target the anchor's peer companies with the anchor delivery as the proof story.
The client is not the problem, the ratio is. A large client inside a diversified book is a gift. The same client at 50 percent of revenue is unpriced risk plus permanent fee leverage against you.
Clientflow runs client acquisition for owner-led recruiting and search firms: data, infrastructure, outreach and reply handling, with a guaranteed floor of held conversations.
Clientflow