Every PPO contract you sign commits your practice to accepting less than your full fee for every procedure billed to that carrier's patients. The question isn't whether you're writing off revenue — you are. The question is whether the patient volume you gain in exchange justifies the write-off. Most practices have never actually done this math.
The Write-Off Problem Nobody Talks About
When a dental practice joins a PPO network, it agrees to accept the carrier's contracted rate as payment in full — which is typically 20% to 50% below the practice's UCR (Usual, Customary, and Reasonable) fee. That difference is written off.
Write-offs are not inherently bad. The economic logic is simple: a lower fee per procedure is acceptable if PPO participation drives enough patient volume to more than compensate for the per-procedure loss. The problem is that most practices joined PPO networks years ago — often when they were building their patient base — and have never revisited whether the original math still holds.
Fee schedules erode over time. Carriers reduce reimbursement rates. UCR fees increase. The write-off percentage grows. And practices absorb this quietly because they've never built a system to catch it.
The Three Numbers You Need
A proper PPO participation analysis requires three figures for each carrier:
- Total annual production billed to that carrier's patients — what you charged at full UCR fee
- Total annual collections from that carrier — what you actually received (insurance payments + patient copays)
- Total write-offs — the difference between the two
Your practice management software can generate these figures by carrier if it's set up correctly. If you've never pulled this report, do it now for your top five carriers. The results are almost always surprising.
Net Production = Collections − (Overhead Rate × Collections)
Break-Even Volume = Fixed Overhead ÷ Net Production Per Visit
What a Healthy Write-Off Rate Looks Like
There is no universal acceptable write-off percentage — it depends on your practice's overhead rate, payer mix goals, and market. That said, industry benchmarks suggest:
- Under 20% write-off: Generally healthy. The PPO discount is modest and volume-driven revenue offsets it comfortably.
- 20–35% write-off: Acceptable if the carrier drives significant patient volume and your overhead is controlled. Warrants monitoring.
- 35–50% write-off: Concerning. Each procedure at this discount level requires high volume to remain profitable. Review participation status.
- Over 50% write-off: Almost never sustainable. A practice writing off more than half its UCR fee on every procedure for a given carrier is likely losing money on those patients after overhead.
The Overhead Factor Most Practices Miss
Write-off percentage alone doesn't tell you whether PPO participation is profitable — you have to factor in overhead. A practice with 65% overhead and a 35% write-off on a given carrier is collecting 65 cents on the dollar of UCR, but spending 65 cents of that on overhead — leaving almost nothing in net production.
Practice UCR fee for D1110: $120. Humana contracted rate: $69 (42.5% write-off). Overhead rate: 68%. Net production per D1110: $69 × (1 − 0.68) = $22.08. At 30 Humana cleanings per week, annual net production from D1110 alone: $34,445. That's before factoring in chair time opportunity cost and billing overhead.
When Dropping a Carrier Makes Sense
Dropping PPO participation is a significant decision with real revenue risk — but it's sometimes the right one. The conditions that favor dropping a carrier:
- The carrier represents less than 8–10% of your total patient base (low dependency risk)
- Write-off rate exceeds 40% and the carrier has reduced rates in recent years without notice
- Your practice has a strong recall system and is confident a meaningful percentage of patients will follow you out-of-network
- Your market has multiple competing PPO-heavy practices — meaning the patients you lose will easily be replaced by non-PPO patients as your marketing improves
Before dropping any carrier, model the patient retention scenario conservatively. Assume you retain 40% of affected patients as out-of-network. Calculate whether the higher per-procedure revenue from those patients (billed at UCR) outweighs the volume loss from the 60% who leave.
The Fee Schedule Monitoring Imperative
Whether you stay in-network or drop a carrier, you cannot make sound participation decisions without current fee schedule data. Carriers change rates annually — sometimes significantly — and most practices have no system to detect those changes until months after they take effect.
A practice that negotiated strong rates in 2022 may be operating on a fee schedule that has eroded 12–15% since then through incremental annual reductions. The write-off math that justified participation four years ago may no longer hold — but without monitoring, you'd never know.
This article is for informational purposes only. PPO participation decisions should be made with complete, current data specific to your practice. Consult a dental practice management consultant or your accountant before making significant payer mix changes.