LOP in Medical Billing: Risks, Revenue Impact, and How Providers Should Handle It

What is LOP in Medical Billing?

LOP in medical billing stands for letter of protection. It is a written agreement, almost always drafted by a personal injury attorney on behalf of an injured patient, that asks a provider to deliver care now and wait for payment until the patient's legal claim resolves. In exchange, the attorney agrees to protect the provider's balance out of any settlement or judgment before the remainder is disbursed to the client.

That is the whole letter of protection meaning in one sentence: treat first, get paid when the case pays.

Who Signs and What Each Party Promises

A properly constructed LOP is a three-party arrangement.

• The patient acknowledges the charges are their personal responsibility and authorizes their attorney to pay the provider directly from any recovery.
• The attorney agrees to withhold the provider's balance from settlement funds held in trust and disburse it before releasing the client's share.
• The provider agrees to render medically necessary care, defer collection activity while the case is pending, and supply records and billing documentation as the case progresses.

The detail that trips up practices is that an attorney letter of protection usually does not make the attorney personally liable for the bill. The attorney's obligation is procedural: hold and pay from proceeds. If there are no proceeds, that obligation is generally satisfied and the balance falls back on the patient, who by definition could not pay in the first place.

Where LOPs Show Up Most

Letter of protection personal injury cases cluster in motor vehicle accidents, slip and fall claims, premises liability, and injuries falling outside workers' compensation. Clinically, the heaviest volume lands in orthopedics, pain management, neurology, physical therapy, chiropractic, imaging, and ambulatory surgery centers. For those specialties, LOP accounts are not an edge case. They can become a meaningful slice of total accounts receivable, and they behave nothing like the rest of the book.

LOP vs. Medical Lien: What Providers Should Know

Providers, attorneys, and billing staff often use "letter of protection" and "medical lien" interchangeably. They are not the same instrument, and the difference decides whether you get paid when a case is underfunded.

A letter of protection is a contract. Its force comes from the agreement itself and from the attorney's professional obligations around client trust funds. A medical lien is a claim against the settlement proceeds themselves. Statutory liens exist because a legislature created them, and they carry strict perfection requirements: filing in the right office, serving notice on specific parties, and doing both inside a statutory deadline. Miss a step and the lien is unperfected, which often means unenforceable.

Two takeaways follow. First, statutory and federal recovery rights sit ahead of a contractual LOP: Medicare Secondary Payer conditional payment recovery, state Medicaid third-party liability recovery, ERISA plan reimbursement, perfected hospital liens, and child support arrears are generally satisfied before a physician group's letter. Second, a state that permits provider liens may give you a stronger position than an LOP for the same care, so ask healthcare counsel which instrument your state actually supports before standardizing on one.

How LOP Billing Differs from Insurance-Based Billing

Everything your billing team knows about payer workflows stops applying the moment an account is flagged LOP. There is no payer, no contract, no adjudication, and no remittance advice. The account is a receivable backed by a lawsuit.

Because there is no fee schedule, LOP charges are billed at full rate, which makes the gross receivable look attractive and eventual realization look disappointing. Because there is no 835, there is no automated posting and no denial code telling you what went wrong. Because there is no timely filing limit, nothing forces the account forward, and a file with no deadline is the file nobody touches.

There is also a compliance layer that routine medical billing workflows never encounter. If the patient has commercial coverage, Medicare, Medicaid, auto medical payments coverage, or personal injury protection in a no-fault state, your payer contracts and state law may require you to bill that coverage first. Declining to bill available insurance in order to preserve a full-charge LOP balance can breach a participation agreement and, for government beneficiaries, create exposure far beyond a contract dispute.

How the LOP Billing Process Works

LOP billing works only when it is a defined workflow with owners and checkpoints.

1. Receive and review the letter. Nothing gets scheduled as an LOP account until the letter is in hand and checked against your acceptance policy.
2. Verify representation and coverage. Confirm the attorney of record, date of injury, case type, and what coverage exists: bodily injury limits, uninsured and underinsured motorist coverage, medical payments coverage, PIP, and any health plan. A mature insurance eligibility verification process already has the muscle for this step.
3. Bill primary coverage where required. Those claims run on their own filing clock, which does not pause for the lawsuit.
4. Execute the agreement. Obtain patient and attorney signatures, add your provider-side terms, and store the executed copy against the account.
5. Register the account correctly. Assign a distinct financial class so LOP balances never blend into standard payer aging.
6. Document to litigation standard. Notes need mechanism of injury, objective findings, causation language, functional limitations, and prognosis. This documentation is evidence, and weak notes shrink the settlement your balance is paid from.
7. Send itemized statements on a cadence. Firms build demand packages from what they have on file. A balance the firm never received is a balance never demanded.
8. Respond to records and narrative requests, and charge for them under a published fee schedule where state law allows.
9. Track case milestones: treatment complete, demand sent, suit filed, mediation, settlement, disbursement.
10. Negotiate at settlement against a pre-approved reduction matrix rather than improvising.
11. Close cleanly. Sign the release only after funds clear, post the payment, and record the write-down in its own adjustment category.

When Should a Practice Accept an LOP?

Accepting letters of protection is a business decision, not a clinical one.

LOPs Tend to Make Sense When

• Your specialty naturally serves injury patients and turning them away leaves capacity unused.
• You have open schedule capacity, so the marginal cost of the visit is low.
• Your balance sheet can absorb receivables that may not convert for a year or longer.
• You work with a small set of firms whose payment history you can verify.
• Someone owns LOP follow-up as a named responsibility.

LOPs Are Usually a Poor Fit When

• Cash flow is tight and payroll depends on current collections.
• The plan involves high-cost procedures, implants, or facility fees, concentrating large exposure on one uncertain claim.
• Liability is genuinely disputed or comparative fault is a live issue.
• Available policy limits are low relative to what treatment will cost.
• Other providers already hold LOPs on the same case and will compete for the same pool.

Treat LOP capacity as a fixed budget rather than an open door. Decide annually how much of your receivables you will place in contingent status, then evaluate each new letter against the room remaining. Practices that skip this usually discover the problem only when the aging report has quietly restructured itself.

How to Evaluate an LOP Before Accepting It

Weak letters are weak in consistent, recognizable places. Read the document before you read the referral.

Check the Language of the Letter

• Does the attorney agree to withhold and pay, or only to notify? "The attorney will honor and protect this balance from settlement proceeds" is meaningfully stronger than "the client authorizes payment."
• Does the patient acknowledge personal responsibility? Without the patient's signature, a failed case may leave nothing enforceable.
• What happens if the attorney withdraws or is discharged? The letter should require notice and survive substitution of counsel.
• Is there a forced reduction clause? Some letters obligate you to accept whatever pro rata share the attorney allocates, converting your bill into someone else's variable.
• Are records fees, narrative reports, interest, and testimony time addressed? Silence usually means unpaid.

Check the Case and the Firm

• Liability posture: admitted, disputed, or shared fault.
• Available coverage, including whether other claimants share the same policy.
• Injury severity relative to the treatment plan you are proposing.
• Case stage: pre-suit demand, filed suit, or scheduled mediation.
• The firm's payment history with your practice, including how deeply it historically asked you to reduce.
• Whether the firm provides a written accounting to providers at disbursement.

Practices that maintain a simple firm scorecard across these points decide far better than practices deciding letter by letter. Apply the same evidence discipline you would bring to a billing audit: score the pattern, not the anecdote.

Financial Risks of LOP Billing for Healthcare Providers

LOP billing is a form of unsecured lending. The practice delivers a service, funds it with working capital, charges no interest, and accepts repayment terms controlled by a third party.

Payment is contingent, not delayed. If liability fails or the defendant is judgment proof, the balance does not arrive late. It does not arrive.

Settlement reductions are the norm. When recovery is smaller than combined medical balances, every provider is asked to take less. Your position depends on documentation, relationship, and whether you have a policy or are improvising.

Priority claims come first. Government recovery rights, ERISA reimbursement, and perfected hospital liens are satisfied ahead of a contractual LOP. A case that looked adequately funded can leave nothing for junior claimants.

Timelines run in years. Long-dated receivables tie up capital that could fund staff or equipment, and that opportunity cost is real even when the account eventually pays in full.

Concentration is dangerous. Heavy exposure to one firm, one carrier, or one accident event turns ordinary business risk into a single point of failure.

Reported A/R becomes misleading. Carrying LOP balances at full billed charges overstates receivables, distorts net collection rate, and inflates days in A/R. Anyone evaluating the practice for a sale or a loan will discount those balances heavily. Practices that have watched aging metrics distort their view of performance will recognize the pattern in our behavioral health A/R turnaround.

Compliance exposure is easy to create accidentally. Routinely waiving patient responsibility, skipping available insurance, or entering arrangements where value flows in exchange for referrals can create problems that dwarf the receivable.

Common LOP Billing Mistakes That Cost Providers Revenue

Most LOP revenue loss is self-inflicted.

1. Treating on a verbal or unsigned letter. A promise over the phone is not an agreement.
2. Collecting only the attorney's signature, leaving no one to bill if the case fails.
3. Skipping available primary coverage. MedPay, PIP, and health plan claims have filing deadlines that expire while the lawsuit continues.
4. Letting LOP accounts sit in standard aging. Blended buckets corrupt your metrics and guarantee the accounts are ignored, because they never trigger a normal follow-up rule.
5. Going silent between visits. Balances not in the demand package are not in the settlement.
6. Never reconfirming representation. Clients change lawyers and firms withdraw. Learning that at settlement is learning too late.
7. Documenting like a routine office visit. Notes that omit mechanism of injury and causation weaken the claim your payment depends on.
8. Sending LOP balances to collections, which usually breaches the letter and destroys the referral relationship.
9. Ignoring the underlying statute of limitations. If the patient's claim expires unfiled, the funding source disappears.
10. Ad hoc reductions. Staff negotiating without a matrix discount inconsistently, and the practice never learns its real realization rate.
11. Miscategorizing the write-down as a contractual adjustment, which hides the true cost of the program.

Coding and documentation defects are as expensive here as on the payer side. The corrective pattern is visible in our orthopedic claim rejection cleanup, where fixing the front end mattered more than working the back end harder.

Best Practices for Managing LOP Accounts in Your Revenue Cycle

Treat the LOP book as its own portfolio, with its own rules, metrics, and owner.

Write a Policy Before the Next Letter Arrives

Put acceptance criteria in writing and have healthcare counsel review them: which case types you accept, maximum exposure per case and per firm, required letter language, who signs off, and who may negotiate reductions and within what range. One page prevents most of the mistakes above.

Segregate and Instrument the Portfolio

Give LOP accounts a dedicated financial class and report them separately. Age them in quarters, not 30-day buckets, because 30-day buckets are meaningless across a two-year cycle. Maintain a register covering patient, date of injury, firm, case status, last contact, statute of limitations date, and balance. Then track realization rate and average months to payment. Those two numbers tell you whether the program is worth running.

Reserve Against Reality

Book LOP receivables at expected realization based on your own history, not at billed charges. Accurate reserves protect cash planning and make financial reporting defensible. It is the same discipline that underpins effective accounts receivable recovery elsewhere in the practice.

Run a Fixed Follow-Up Cadence

Contact every open file on a schedule with an itemized balance, a case status request, and confirmation that representation continues. Consistency beats intensity. Administrative support such as virtual medical assistance suits this well, since the work is high-volume and template-driven.

Automate What Repeats

Status letters, balance updates, milestone reminders, and statute of limitations alerts are rules-based tasks. They belong in an automation layer rather than on someone's calendar, which is where they get skipped during a busy month.

Prepare the Settlement Conversation Early

Before the demand goes out, assemble the itemized ledger, the documentation supporting medical necessity and causation, and your reduction range. Organized providers are reduced less than reactive ones.

State-Specific LOP Regulations Providers Should Know

LOP practice is governed by state law and the variation is significant. What follows is general orientation, not legal advice. Confirm the rules for every state you operate in with qualified healthcare counsel.

Florida

Florida's 2023 tort reform legislation put letters of protection under the microscope. The framework requires an LOP to be disclosed in litigation, along with whether the claimant was referred to the provider by their attorney, and it changed how past medical charges may be presented as evidence of damages, steering admissible amounts toward what was actually paid or toward reimbursement benchmarks rather than gross billed charges. For letter of protection Florida cases, billed charges alone no longer carry the weight they once did, and referral relationships are now visible to the other side.

Texas

Texas limits recovery of medical expenses to amounts actually paid or incurred, and Texas courts have allowed discovery into the reasonableness of charges, including comparisons to negotiated rates. Practices handling letter of protection Texas matters should expect charge levels to be examined rather than accepted. Texas also has a hospital lien statute, but its protection reaches only the provider categories the statute names, which does not automatically include an independent physician practice.

Themes That Recur Across States

• Lien eligibility varies. Some states extend statutory lien rights beyond hospitals to physicians and other providers; many do not.
• Perfection requirements are strict. Where liens exist, filing location, notice recipients, and deadlines are mandatory rather than advisory.
• Assignment of personal injury claims is restricted in many states, which is exactly why LOPs are drafted as directions to pay from proceeds rather than as assignments.
• No-fault and PIP states change the order of operations. Where PIP is primary, it typically must be billed and often exhausted first.
• Records fee caps are common, limiting what you can charge for the record production a case generates.
• Government payer recovery is superior. Medicare Secondary Payer and state Medicaid third-party liability rights apply regardless of what your letter says.

If you operate across state lines, do not run one LOP template everywhere. Build a state matrix and let local rules drive the document.

How CureMed Helps Practices Handle LOP Billing with Confidence

LOP accounts fail in the gaps: the letter nobody reviewed, the primary coverage nobody billed, the balance update nobody sent, the settlement nobody prepared for. CureMed closes those gaps by treating LOP as a managed segment of the revenue cycle rather than an exception queue.

For practices in orthopedics, pain management, neurology, and other injury-heavy specialties, our teams support:

• Intake and verification: confirming representation, identifying MedPay, PIP, motorist coverage, and health plan benefits, and flagging where primary billing is required before an account is classified as LOP.
• Correct account setup: a separate financial class so LOP balances stay visible, reportable, and distinct from payer A/R.
• Documentation and charge integrity: review of coding, modifier use, and supporting documentation so the ledger holds up when the other side examines it.
• Structured follow-up: scheduled itemized statements and status requests to firms, with representation and milestone checks built into the cadence.
• Portfolio reporting: realization rate, average months to payment, exposure by firm, and statute of limitations tracking, delivered in a format ownership can act on.
• Settlement support: assembling the ledger and documentation ahead of the demand so reduction conversations start from a defensible position.

That work sits alongside the rest of our revenue cycle management services, so LOP accounts are handled in the same system, by the same standards, as everything else you bill. The result is a clearer picture of what your injury-case volume is actually worth.

If letters of protection are a growing part of your book and nobody owns them, that is the problem worth fixing first. Talk to the CureMed team about a review of your LOP portfolio and the rest of your revenue cycle.