Can a doctor bill you a year later after insurance? The filing deadlines that decide it

Two dates on every late bill

Medicare measures timeliness by the day the claim lands at its contractor. Chapter 1 of the Medicare Claims Processing Manual says Medicare denies a claim for untimely filing if the receipt date applied to the claim exceeds 12 months, or 1 calendar year, from the date the services were furnished. Commercial plans and state statutes use the same logic with different numbers: the clock runs from the service date (or discharge) to the date the payer receives the claim.

That gives a late bill two dates worth knowing. One is the service date, printed on the bill. The other is the date the provider first submitted the claim to your plan, which is printed nowhere on a patient statement and has to be asked for. A statement that arrives in month eleven can sit on top of a claim the plan received in week two and processed slowly, or on top of a claim nobody sent until month ten. The two cases look identical in your mailbox and are opposite in who should pay.

Most late bills are the first kind. A claim goes in on time, the plan asks for records, a second insurer has to process it, or someone appeals, and the provider waits for the final answer before billing your share. A deductible or coinsurance amount that arrives late after a timely claim is still a deductible or coinsurance amount. The filing rules below matter for the second kind: the claim that went in late, or never went in at all, and came back to you as a full charge.

Claim-filing limits by payer and state, checked October 30, 2026

Each row comes from the official text of the rule: the eCFR for federal regulations, the CMS manual for Medicare processing, and each legislature's own statute site. The limit is how long a provider has to get the claim to the payer. The last column is what the text says happens when it misses.

Sources: eCFR, CMS Medicare Claims Processing Manual chapter 1, Texas Legislature statutes site, Online Sunshine (Florida Statutes 2026), Maryland General Assembly statute text. Read and checked October 30, 2026. Provider contracts can set different deadlines where a statute allows it.

Three patterns stand out in the table. The deadlines run from 95 days to a full year, so a bill that would be routine under Medicare can be months past a Texas plan's window. The Maryland row is a different kind of rule: section 15-1005(e) says a plan must permit "a minimum of 180 days" to submit a claim, so it limits how short a plan's deadline can be rather than setting one. And Florida's clock does not start until two things have happened, the service and the provider having "the correct name and address" of your insurer, which matters if you did not hand over a card at the visit.

A note on the Medicaid row, because it is widely misquoted. Section 447.45 of title 42 is titled "Timely claims payment" and sits in the Medicaid payment rules. Its paragraph (d)(1) says the Medicaid agency must require providers to submit all claims no later than 12 months from the date of service. It binds state Medicaid programs. It does not set a 12-month limit for employer, Marketplace or other commercial plans, and a page that cites it for a commercial claim is applying it outside its scope.

The table also leaves things out on purpose. Medicare Advantage plans, Medicaid managed care plans and commercial plans in other states set deadlines through provider contracts, state rules and plan documents that this table does not reproduce. If your plan is not in a row, the plan itself can tell you its claim-filing limit for the provider's network status, and an in-network provider's contract will have one.

One service date, run through every deadline

Take an invented office visit on September 15, 2025, with a statement for the full charge arriving on October 20, 2026, 400 days later. The table applies each rule's own counting method to that one date. The service date and the bill date are illustration inputs; the counting comes from the rule text.

Counting notes: the Texas chapter 146 date counts the month after the service month as the first month, so the 11th month after September 2025 is August 2026. Day counts are calendar days. September 15, 2026 falls on a weekday, so the Medicare nonworkday rule in 42 CFR 424.44(c) does not move it. Rules read October 30, 2026.

The arithmetic does not settle the account. It tells you which question to ask. A bill dated 400 days after the visit is past every limit in the table, so the useful question to the billing office is a factual one: on what date did my plan first receive this claim? If the answer is within the window and the plan applied the amount to your deductible, the bill is late but probably legitimate. If the answer is a date after the window, or there is no answer because the claim was never sent, the next section decides who bears it.

Who absorbs a missed deadline: a decision rule

Work down the list and stop at the first rule that fits. Each step quotes the text it rests on, because the wording, not a summary of it, is what a billing office or regulator will read.

1. Was the claim actually late? Ask for the submission history. If the plan received the claim inside its limit, timely filing is not the issue, and the bill is your cost share or a processing dispute. Stop here and read the EOB.
2. Original Medicare, and the provider knew or should have known you had Medicare. The claims manual, chapter 1, section 70.4: where the beneficiary request for payment was filed timely, or would have been filed timely had the provider taken action to obtain one from a patient it knew or had reason to believe might be a beneficiary, "but the provider is responsible for not filing a timely claim, the provider may not charge the beneficiary for the services except for such deductible and/or coinsurance amounts as would have been appropriate if Medicare payment had been made." Your share stays your share. The rest does not move to you.
3. Medicaid enrollee, provider participates in Medicaid. 42 CFR 447.15 requires the state to limit participation to providers who accept, as payment in full, the amounts paid by the agency plus any cost sharing the plan requires. The state Medicaid agency and its provider rules decide how that applies to a claim denied as late; ask the agency in writing rather than paying the provider's full charge.
4. In-network provider, state-regulated HMO or insurer policy. Look for a statutory hold-harmless. Texas Insurance Code section 843.361 requires every HMO-provider contract to "specify that the physician or provider will hold an enrollee harmless for payment of the cost of covered health care services if the health maintenance organization does not pay the physician or provider for those services." Texas sections 843.337(b) and 1301.102(d) say a physician or provider who fails to submit a claim in compliance "forfeits the right to payment." Florida section 641.3154(4) says no provider, under contract or not, may collect from, sue or report to a credit agency an HMO subscriber for services the HMO is liable for. Other states' codes and the provider contract may say similar things; ask the plan to confirm in writing.
5. Texas, any health benefit plan. Civil Practice and Remedies Code section 146.003(a): a provider who misses the section 146.002 billing deadlines "may not recover from the patient any amount that the patient would have been entitled to receive as payment or reimbursement under a health benefit plan or that the patient would not otherwise have been obligated to pay had the provider complied." Subsection (b) extends that bar to family members who would otherwise be responsible. Chapter 146 defines a health benefit plan broadly, including HMO evidence of coverage, multiple employer welfare arrangements, workers' compensation and motor vehicle personal injury protection.
6. The delay started with you. If you gave no insurance information, gave the wrong card, or told the office you were paying yourself, the rules above may not protect you. The Medicare text turns on whether the provider knew or had reason to believe you were a beneficiary; Florida's clock waits for the provider to have the insurer's correct details. The fix is to get the claim filed now, under any late-filing exception the plan offers, before treating the balance as yours.
7. None of the above fits. The plan's EOB code and the plan's written answer become the evidence. A plan statement that the amount is a provider write-off is the document to send to the billing office.

Two limits apply all the way down. None of these rules erases a deductible, copay or coinsurance amount that would have applied if the claim had been paid; the Medicare manual says so expressly, and the Texas chapter 146 bar is written around what the plan would have paid. And none of them helps with a service the plan would not have covered on time either; a non-covered service denied late is still a non-covered service.

Reading the EOB when the plan says "time limit"

When a plan denies a claim as late, the denial usually reaches you on an explanation of benefits before the provider's next statement does. Payers describe adjustments with codes from national lists, and the one for this situation is claim adjustment reason code 29, which the X12 list words as "The time limit for filing has expired." Your EOB may print the code, the plan's own remark code, or only a sentence, so look for the words "timely filing," "filing limit" or "time limit."

The two letters in front of the code carry the answer to who pays. The Medicare Claims Processing Manual, chapter 22, section 60.1, defines CO, Contractual Obligations, as a group code used when "a contractual agreement between the payer and payee, or a regulatory requirement, resulted in an adjustment," and adds that these adjustments are "generally" considered a write-off for the provider and not billed to the patient. PR, Patient Responsibility, is the group code for an amount that may be billed to the patient. So the same reason reads two ways:

Sources: X12 claim adjustment reason code list (code 29, start date January 1, 1995); Medicare Claims Processing Manual, chapter 22, section 60.1. Checked October 30, 2026.

The full reading method for these lines, including the allowed amount and the remark codes, is in the EOB field-by-field walkthrough. For a timely-filing case, the line you need is the one whose service date matches the bill, and the two facts you need from it are the group code and the patient-responsibility amount.

Why a legitimate bill can still show up a year later

A late statement is not proof of a late claim. Several ordinary processes push a valid bill past the point where you have forgotten the visit, and some of them come with their own deadlines that protect you in a different way.

A second payer had to go first or last

When two plans cover you, the primary processes the claim, then the secondary, and only then does the provider know what is left. Florida's statute builds this into its timeline: claims to a secondary insurer must be mailed or electronically sent "within 90 days after final determination by the primary insurer." A secondary claim filed inside that window is timely even when it is many months after the service.

The plan took its payment back

Sometimes the claim was paid on time and then reversed. A plan that later decides it overpaid, or that you were not covered on the service date, recovers the money from the provider, and the provider rebills you. State law limits how long that window stays open:

• Texas: An HMO or PPO insurer may recover an overpayment only if it sends written notice with reasons not later than the 180th day after the provider receives the payment. (Tex. Ins. Code secs. 843.350(a), 1301.132(a))
• Florida: An insurer's overpayment claim must reach the provider within 30 months after the insurer paid, except for providers convicted of fraud. (Fla. Stat. s. 627.6131(6))
• Florida: An insurer may not retroactively deny a claim for the insured's ineligibility more than 1 year after it paid the claim. (Fla. Stat. s. 627.6131(11))

If a rebill follows a recoupment, ask the provider for the date of the plan's recovery notice and the reason, and compare them with the limits for your state. A Texas recovery whose notice came 200 days after the payment, for example, falls outside the 180-day condition in the statute.

Coverage was granted after the fact

Medicare and Medicaid both cover some services retroactively, which means a claim can become fileable long after the visit. The Medicare regulation recognizes this directly. Medicare extends the filing period through the last day of the 6th calendar month after the month of notice when the delay came from a Medicare error, retroactive Medicare entitlement, or a Medicaid or Medicare Advantage recovery made 6 months or more after the service. (42 CFR 424.44(b).) Requests based on a Medicare error cannot be granted more than 4 years after the service date. If your Medicaid approval reached back to cover a visit, the retroactive Medicaid guide explains the three-month look-back and how to get a provider to bill Medicaid for an old date.

An appeal or records request was pending

If the plan asked for medical records or you appealed a denial, the final answer and the bill that follows it can come many months after the service. The claim was timely; the decision was slow. Maryland's statute addresses the provider side of this, requiring plans to give a provider at least 90 working days after a denial to appeal. Your own appeal rights run separately and are set out in the denial appeal guide.

Where state claim-filing law stops

The state rows in the table come from insurance codes, and each code says which plans it reaches. Florida section 627.6131(15) says that section applies "only to a major medical expense health insurance policy" offered by a licensed group or individual insurer, including preferred and exclusive provider policies. Texas chapter 1301 applies, by section 1301.0041, to a preferred provider benefit plan in which an insurer provides coverage "through the insurer's health insurance policy." A plan that an employer funds itself is not an insurer's policy, so before relying on a state code, ask your employer or the plan whether your coverage is insured by a licensed carrier or paid from the employer's own funds. The answer is usually in the plan's summary documents.

Texas chapter 146 is the exception that reaches further. It is in the Civil Practice and Remedies Code, not the Insurance Code, and its definition of a health benefit plan in section 146.001 covers any "plan or arrangement under which medical or surgical expenses are paid for or reimbursed." Section 146.002(b) still lets a contract between the provider and the plan set the payer deadline, and subsection (c) defers to a federal regulation or state rule for Medicare and Medicaid, but the bar on recovering the plan's share from the patient in section 146.003 applies to a provider who misses whichever date governs.

Medicare Advantage plans are a separate track again. The 42 CFR 424.44 limit is written for Medicare fee-for-service claims, and the manual describes it that way. An Advantage plan's filing limit for its network providers comes from its provider contracts. Ask the plan for the limit that applied to your provider and whether the denied amount is assigned to you or written off.

Disputing a year-old bill: a letter built on dates

A dispute over a late claim is a dispute about dates, so the letter should be built from them. Collect four documents before writing: the statement, the EOB for that service date (or the plan's written confirmation that none exists), the plan's claim-filing limit in writing, and the submission history from the billing office. With those, the letter can be short.

The letter itself needs only the account number, the service date, the plan's receipt date (or the absence of a claim), the filing limit, the EOB group code, and one request: adjust the balance to the cost share the plan assigned to you. Quote the rule that fits from the decision list above, word for word, rather than describing it. Keep a copy, and send it in a way that shows the date it arrived.

If the plan confirms the claim was filed late but marks the amount PR, the dispute moves to the plan. Ask for the plan term that assigns a provider's late filing to the member. Florida's statute gives insureds one more lever in subsection (13): on written notice from an insured, the insurer must investigate a claim of improper billing by a physician, hospital or other provider, and if it finds the insured was improperly billed, notify the insured and the provider of its findings. The statute frames that review around whether the insured was billed only for services actually received, so it fits a bill for the wrong service better than a pure timing dispute.

Paying first and arguing later is the expensive order, because getting money back from a billing office is slower than not sending it. Pay any part you agree is your cost share and dispute the rest in writing. If the account has already gone to a collector, the 30-day validation window in the medical-bill collections guide runs alongside everything here, and the dispute letter should go to the collector as well as the provider.

Two longer-range limits belong to other pages. How long a provider or collector has to sue over an unpaid balance is a statute-of-limitations question under state law, separate from claim filing, and what happens if you don't pay a hospital bill walks through the collection stages and the court process. Whether an old medical balance can appear on a credit report, and when it must come off, is in the medical debt credit report guide.

Where the deadline rules run out

Timely filing rules protect against one specific failure: a provider who could have been paid by your plan and was not, because of its own delay. They are not a general shield against late bills. An uninsured visit has no plan deadline. A service your plan excludes is excluded whenever the claim arrives. A deductible is owed whether the bill comes in a month or in eleven. And a balance that is genuinely yours, but larger than you can manage, is a negotiation and financial assistance question; the bill negotiation guide and the hospital financial assistance guide cover those.

Within its lane, though, the rule is strong, and it is the reason a year-old bill deserves one phone call before it gets a check. Ask the billing office for the date the claim first went to your plan, put that date beside the limit in the table, and let the gap tell you which letter to write. More disputes about late bills in the medical bills section follow the same pattern: the paperwork usually holds the answer, and the date is the first thing to find in it.

Late medical bills: questions readers ask

The deadline table's legal text, by payer

• eCFR, 42 CFR 424.44, time limits for filing Medicare claims, exceptions in paragraph (b), nonworkday rule in paragraph (c). Checked October 30, 2026.
• CMS, Medicare Claims Processing Manual, chapter 1, sections 70 to 70.4 (receipt date, untimely filing denial, provider may not charge the beneficiary). Checked October 30, 2026.
• eCFR, 42 CFR 447.45, Medicaid timely claims payment, paragraph (d)(1), and 42 CFR 447.15, acceptance of state payment as payment in full. Checked October 30, 2026.
• Texas Legislature, Civil Practice and Remedies Code chapter 146, sections 146.001 to 146.004, as amended by H.B. 4145 (2025). Checked October 30, 2026.
• Texas Legislature, Insurance Code chapter 843, sections 843.337, 843.350 and 843.361, and chapter 1301, sections 1301.0041, 1301.102 and 1301.132. Checked October 30, 2026.
• Florida Legislature, Online Sunshine, 2026 Florida Statutes, section 627.6131, section 641.3155 and section 641.3154. Checked October 30, 2026.
• Maryland General Assembly, Insurance Article section 15-1005, subsection (e). Checked October 30, 2026.
• CMS, Medicare Claims Processing Manual, chapter 22, section 60.1, group codes CO and PR; X12, Claim Adjustment Reason Codes, code 29. Checked October 30, 2026.

General billing information, not legal, medical or insurance advice. Statutes change and provider contracts can vary deadlines where the law allows; the plan's written answer about your claim controls. Confirm any balance in writing before you pay it.