BUSINESS BITES - AOB vs EOB
They look almost identical, both end in “OB,” and they get mixed up at the front desk constantly. But an assignment of benefits and an explanation of benefits are completely different documents that show up at opposite ends of the same claim. Getting them straight prevents collection headaches and catches money you’re owed. Here’s the distinction, and what your team should actually do with each.
The one-line version: the AOB is an instruction the patient gives going in — it tells the plan who to pay. The EOB is the report the insurer sends coming back — it explains what the plan decided. One directs the money; the other accounts for it.
Assignment of benefits: set a policy and mind the catch
An assignment of benefits is the patient’s authorization directing the plan to send payment to the dentist instead of to them. On the 2024 ADA Dental Claim Form it’s the signature in Box 37 — and it only controls where the payment goes; it does not create a contract with the insurer or change what the patient owes.
It matters most when you’re out-of-network. In-network contracts already require the plan to pay you directly. Out-of-network, without an assignment the reimbursement check may go to the patient — and now you’re chasing them for money the insurer has already paid out.
The catch is that the AOB isn’t always honored. While about two dozen states (as of mid-2024) require plans to pay the dentist directly when the patient authorizes it, regardless of network status, self-funded employer plans governed by federal ERISA law may claim exemption from those state rules and pay the patient anyway. Since you usually can’t tell from a patient’s card whether their plan is self-funded, set a clear front-desk policy: either collect in full up front, or take the assignment and verify how that specific plan handles it.
Explanation of benefits: read it, don’t just file it
An explanation of benefits is the statement the insurer sends after it processes a claim: showing what you billed, the plan’s allowed amount, what it paid, the adjustment or write-off, and the patient’s responsibility. It looks like a bill, but it isn’t one; no money is attached. It’s a record of what the plan decided.
The mistake is treating it as a receipt and filing it. Don’t just check the payment amount — compare the reimbursement against your contracted fee, and review every denial, partial payment, and the remark codes in the fine print, because that’s where the real information lives. A few lines should always make you look twice:
Downcoding — the plan pays for a cheaper procedure than the one you performed, the classic being a posterior composite reimbursed as an amalgam. The plan isn’t judging your clinical work; it’s just paying a lower benefit. If you’re out of network, you can still bill the patient your full fee.
Bundling — distinct procedures combined into a single one for a reduced benefit, such as separate radiographs paid as one full-mouth series (which can also trip the plan’s frequency limits). A procedure listed with no payment beside it is the tell.
A payment that doesn’t match your contract, or a denial whose remark code doesn’t actually explain the reduction.
When a claim wasn’t adjudicated correctly, the fix is to appeal in writing — skipping that step usually bars any further recourse. And even when an appeal doesn’t recover more money, it can keep the patient from assuming you miscoded the claim.
Once Again
The AOB goes in with the claim and decides who gets paid; the EOB comes back after and explains what was paid. Train your front desk to handle the first with a clear, consistent policy, and to actually read the second line by line. Those two habits together protect your collections and your patients’ trust at the same time.
