Underpayment
An underpayment is a claim paid at less than the contract requires. Unlike a denial, it arrives as a payment — so nothing about it looks wrong.
Updated
An underpayment is a claim the payer paid, but at less than the contracted rate. It is not a refusal to pay and not a denial: the claim was processed and money arrived. It simply arrived short of what the agreement entitled the provider to.
Detecting one requires knowing what the payment should have been. That means holding the contracted rates and comparing each payment against them — without that reference, an underpaid claim is indistinguishable from a correctly paid one.
In practice
Underpayments are the quietest loss in the revenue cycle, and the reason is structural. A denial announces itself with a reason code on a claim that did not pay. An underpayment arrives as a payment, posts without incident, closes the balance, and shows up in reporting as a collected claim. Everything about it looks like success.
They are also easy to mistake for expected contractual adjustments, because both are the difference between what was billed and what arrived. The distinction is the contract: an adjustment down to the contracted rate is the agreement working, and a payment below that rate is the agreement not being honored.
Commonly confused with
- Contractual adjustment: A contractual adjustment is the agreed write-down to the contracted rate. An underpayment is a payment that falls below that rate — expected reduction versus a shortfall.
- Denial: A denial refuses payment and says why. An underpayment pays, says nothing is wrong, and is only visible against the contract.