“Paid” and “Paid Correctly” Are Not the Same Thing

Every month, your billing team posts payments, works the denials they can see, and moves on. The ERA says paid. The balance is zero. Case closed.

Except “paid” only means the payer sent money. “Paid correctly” means they sent the amount your contract says they owe you. Those are two different things, and the gap between them is where clinics quietly lose money — not in dramatic denials, but in claims that looked finished.

Where the money hides

Underpayments rarely look like errors. They look like normal, closed claims. Here are the patterns that show up again and again:

1. The payer is on last year’s fee schedule.

Contracts renew. Fee schedules update. But payers don’t always update what they actually pay. If your contract rate for 99214 went from $131 to $138 in January and the payer kept paying $131 through June, every one of those claims is underpaid by $7 — and every one of them shows a zero balance. Nobody flags it because nothing looks wrong.

2. Modifiers get ignored.

You bill 99213-25 with a procedure on the same day. The contract says the visit is separately payable with modifier 25. The payer’s system drops the modifier and bundles the visit anyway. The claim pays, just $90 light. Your biller sees a paid claim, not a missing modifier.

3. Multiple-procedure discounting is misapplied.

Many contracts say the first procedure pays at 100% and subsequent ones at 50%. That’s normal. What’s not normal is when the payer applies the 50% reduction to the highest-valued procedure instead of the lower ones, or discounts procedures that your contract explicitly excludes from the rule. The math is buried three lines deep in the remit. Nobody recomputes it.

4. Units and bilateral procedures.

A bilateral procedure should pay at 150% of the fee schedule rate. Some payers pay it at 100%. An injection billed with 2 units gets paid for 1. These are single-line discrepancies on otherwise clean claims.

5. New codes default to low rates.

When CPT codes are new or revised, payers sometimes load a placeholder rate — often far below the contracted rate — and never correct it. If you added a new service line this year, check what it’s actually paying against.

How to check this yourself

You don’t need new software. You need a spreadsheet and one afternoon.

1. Export 90 days of paid claims from your practice management system: claim number, payer, CPT code, modifiers, units, billed amount, allowed amount, paid amount.
2. Get your current fee schedules. Call each payer’s provider relations line and ask for the current fee schedule for your top 20 CPT codes. Get it in writing — an email counts.
3. Join the two. For each claim, compute expected payment: fee schedule rate, adjusted for units and modifiers, minus patient responsibility. Compare it to what was actually allowed.
4. Group by payer and CPT. You’re not looking for one-off mistakes. You’re looking for patterns — a specific payer paying a specific code below contract rate, repeatedly. One claim off by $12 is noise. Forty claims off by $12 is a systematic underpayment worth disputing.
5. Flag anything paid more than 5% below expected. Sort by total dollars, not by claim count. Ten dollars times five hundred claims is real money.

What to do with what you find

Document the pattern: payer, CPT, date range, number of claims, total shortfall. Send it to your payer rep with the contract language attached. Payers correct systematic errors faster than one-off complaints because one-off complaints are easy to stall.

And set a calendar reminder to re-pull your fee schedules every year. Contracts renew quietly. Payment systems update loudly or not at all.