Copay & Coinsurance Calculator
Stop guessing at check-in. Enter the allowed amount, remaining deductible, copay and coinsurance, and see the exact patient-versus-plan split, step by step.
“What will I owe today?” is the question every front desk hears — and the one most often answered wrong. This calculator applies a simple, clearly stated model to the allowed amount: the remaining deductible comes first, then the flat copay, then the coinsurance percentage on what is left. The result is an ordered breakdown of what the patient pays and what the plan pays.
Calculate the patient’s share
Why the order matters
Collecting the wrong amount at check-in creates work in both directions: over-collect and you owe the patient a refund; under-collect and the balance ages in AR while statements chase it. The order in this model — deductible, then copay, then coinsurance on the remainder — is the sequence most commercial plans apply to in-network office services, and it is the sequence your eligibility check should confirm. Two cautions keep estimates honest. First, use the allowed (contracted) amount, not your billed charge: coinsurance percentages apply to the allowed amount, and running them against billed charges is the most common reason estimates come out too high. Second, plans vary — some apply the copay instead of the deductible for certain services, some waive the deductible for preventive care, and a few calculate coinsurance before the copay. This calculator states its model openly so you can see when a plan’s actual adjudication differs and why. Pair it with our patient responsibility estimator for a fuller pre-visit picture, and verify benefits on every visit — the deductible figure is only as good as the last eligibility check.
Frequently asked questions
Should I enter the billed charge or the allowed amount?
Always the allowed (contracted) amount. Deductibles, copays and coinsurance are adjudicated against the plan’s allowed amount for the service, which is usually lower than the billed charge. Using billed charges inflates the estimate and leads to refunds and patient complaints.
What if the copay is bigger than what is left after the deductible?
The calculator caps the copay at the remaining balance — a patient never owes more than the allowed amount in total. In that situation the deductible plus the capped copay consumes the whole charge and coinsurance drops to zero.
Does every plan follow the deductible, then copay, then coinsurance order?
No. It is the most common sequence for in-network office services, but plan designs differ: some waive the deductible when a copay applies, some apply coinsurance to the post-deductible balance without a copay, and preventive services are often exempt from cost-sharing entirely. Confirm the sequence during eligibility verification for the specific plan and service.
Disclaimer: This tool is provided for educational and planning purposes only. It is not billing, coding, legal, or financial advice, and it does not replace the rules of any specific payer. Requirements and figures change over time — always verify against current CMS guidance and your own payer contracts before acting on a result.