CPT code 76813: First trimester fetal ultrasound billing guide

CPT code 76813 is the billing code for a first trimester fetal ultrasound performed transabdominally, including nuchal translucency (NT) measurement when performed. OB/GYN and maternal-fetal medicine (MFM) coders report it for the first trimester screening scan, done between roughly 10 weeks and 13 weeks 6 days. Medicare’s 2026 national average payment is about $115.57, with no separate facility rate.

Denials on this code usually start in the report rather than the claim form. An incomplete NT record is the leading trigger, and the wrong 76814 unit count on multiples is close behind.

Key takeaways

CPT code 76813 reports a transabdominal first trimester fetal ultrasound with optional nuchal translucency measurement, distinct from the general first trimester code 76801.

CPT 76814 is the add-on code billed once per additional gestation beyond the first, and it cannot be reported without 76813.

A 76813 report needs the NT value, the CRL, the fetal heart rate, and a saved NT image.

Medicare’s 2026 national average is about $115.57, and the facility and non-facility amounts are identical.

Practice management software like Pabau flags incomplete obstetric documentation before submission and posts remittance data for denial follow-up.

CPT code 76813: Official descriptor and clinical context

The American Medical Association’s CPT code set prints the 76813 descriptor in two parts, separated by a semicolon.

• Ultrasound, pregnant uterus, real time with image documentation, fetal and maternal evaluation, first trimester (less than 14 weeks 0 days), transabdominal approach.
• Single or first gestation.

The parenthetical note adds “including nuchal translucency measurement when performed.” NT measurement is therefore covered by 76813 when it is done, but it is not required to bill the code.

Providers who typically bill this code include OB/GYNs, maternal-fetal medicine specialists, and radiology practices credentialed for obstetric ultrasound. The code sits within the Diagnostic Ultrasound section of CPT and carries no global period (XXX indicator — the global concept doesn’t apply).

CPT 76813 vs 76814: The add-on code relationship

CPT 76814 is the add-on code reported for each additional gestation beyond the first when CPT code 76813 is performed. In a twin pregnancy, for example, you would bill 76813 once (for the first fetus) and 76814 once (for the second). A triplet pregnancy would use 76813 x1 and 76814 x2.

• 76814 cannot stand alone. It requires 76813 as the primary code on the same claim.
• Units matter. Bill 76814 with the unit count matching the number of additional gestations, not as a single line regardless of count.
• Same date of service. Both codes are billed on the same date; splitting them across dates creates a claim edit.
• Documentation must cover each fetus. Separate NT measurements and biometric findings are required for each gestation to support the 76814 units billed.

Coders often miss the unit-per-gestation rule and default to a single 76814 line for all multiples. That underbills twin-and-above pregnancies and can raise audit flags when the delivery record later shows multiple gestations.

CPT 76813 vs CPT 76801: Which first trimester code applies

CPT code 76813 applies when the first trimester ultrasound is performed with a nuchal translucency protocol and the NT is measured. 76801 applies to a standard first trimester ultrasound without the NT component. What was measured and documented decides the code, rather than the equipment in the room.

The Society for Maternal-Fetal Medicine (SMFM) gives direct guidance here. Bill 76813 when the examination includes a compliant NT measurement taken by an NT-credentialed sonographer or physician. Bill 76801 when no NT measurement is performed, even though the gestational age falls inside the first trimester window.

Some payers add a credentialing condition. The NT must be performed by a sonographer holding Fetal Medicine Foundation (FMF) or Nuchal Translucency Quality Review (NTQR) credentials. Check individual payer policies before billing 76813 for an NT scan performed outside a credentialed program.

Documentation requirements for CPT code 76813

Complete documentation is the single biggest risk factor for 76813 denials. Payers routinely audit first trimester screening claims, and a missing NT value or absent image documentation is sufficient grounds for takebacks under post-payment review.

The report for a 76813 encounter must capture all of the following to withstand audit:

• Nuchal translucency measurement: the measured value in millimeters. The measurement must be taken in the correct plane, with a neutral neck position and a sagittal view. Calipers sit on the inner borders of the nuchal space.
• Crown-rump length (CRL): used to confirm gestational age is within the first trimester window
• Fetal heart rate (FHR): documented in beats per minute
• Number of fetuses: required to justify 76814 add-on units if applicable
• Fetal cardiac activity: present or absent notation
• Maternal uterus and adnexa evaluation: brief assessment documented even if unremarkable
• Saved images: at minimum, a standardized NT image with calipers visible, per AIUM practice parameters for obstetric ultrasound

Good documentation habits also mean noting who performed the scan. Many payers require that the NT measurement be performed or supervised by a credentialed provider. Include the performing provider’s name and credential status in the report.

ICD-10 codes used with CPT code 76813

Every CPT code 76813 claim requires a supporting ICD-10 diagnosis code that establishes medical necessity. The most commonly paired codes fall within the supervision of normal pregnancy and prenatal screening categories. Payers validate that the diagnosis code is consistent with a first trimester visit and with the clinical reason for the ultrasound.

Always use the most specific code available. Z34.01 fits a straightforward first trimester supervision visit, while Z36.9 captures the screening intent when NT measurement is the reason for the scan. Z36 on its own is a parent category and will not pay, so a fourth character is always required.

The wider ICD-10-CM code index lists the fourth-character options under each of these parent categories. Use a CPT-to-ICD-10 crosswalk tool to confirm your pairing does not trigger an edit under the payer’s medical policy.

2026 Medicare reimbursement rates for CPT code 76813

The 2026 Medicare physician fee schedule pays CPT code 76813 the same amount in a facility and in an office. This code carries no site-of-service payment differential, so the practice expense RVU does not drop when the scan is done in a hospital. Use the CMS Physician Fee Schedule lookup tool to pull the rate for your own locality.

The payment comes mostly from practice expense, which is what makes the two settings pay alike.

RVU values for 76813 are stable year over year, but the conversion factor changes each January and shifts the dollar amount. The 2026 factor is $33.4009, so a total of 3.46 RVUs pays roughly $115.57 before geographic adjustment. For figures by locality code, use the FastRVU 2026 RVU lookup or pull the CMS data directly.

Payer coverage policies for CPT code 76813

Coverage for CPT code 76813 is broad across commercial payers but comes with medical necessity conditions that vary by carrier. Most major payers cover first trimester ultrasound with NT measurement as a preventive screening benefit when documentation criteria are met. Prior authorization is uncommon for this code alone but may be required when billed alongside high-cost tests on the same date.

• BCBS plans: generally cover 76813 under the prenatal care benefit. Some plans require the performing provider to be NTQR-credentialed and deny the claim when the credential is not on file.
• Aetna: covers NT measurement as part of first trimester combined screening. Aetna CPB 282 sets the detailed criteria, including gestational age windows and interpretation requirements.
• Highmark: covers 76813 under medical policy X-51-010. The policy requires the NT value and the CRL in the report.
• United Healthcare: covers first trimester screening ultrasound as a preventive service under the ACA. Confirm whether the plan year includes NT measurement in its preventive benefit tier.

Checking eligibility before the appointment confirms whether 76813 is a covered benefit and whether a deductible applies. Under ACA-compliant plans, preventive screenings are often covered at 100% with no cost share. That holds only when the provider is in-network and the plan year has not reclassified the benefit.

Billing CPT 76813 with cfDNA screening

Same-date billing of CPT code 76813 and cfDNA (cell-free DNA) screening is one of the most contested scenarios in maternal-fetal medicine. SMFM guidance treats 76813 and cfDNA testing as clinically distinct services. Both may be billed on the same date when each is performed and separately documented.

Payer policies vary enough, however, that blanket co-billing without a payer-specific review creates meaningful denial risk. Key points from SMFM coding guidance:

• 76813 and cfDNA are not bundled by CMS. No NCCI edit bundles the cfDNA lab code (81420 or 81507) with 76813, so no modifier is required from a CMS perspective.
• Commercial payer bundling policies differ. Some BCBS plans and Highmark policies do apply coverage limitations when 76813 and cfDNA are billed on the same date. Review the payer’s antenatal screening medical policy directly.
• 76813 vs 76801 when cfDNA is ordered. SMFM notes one exception here. When cfDNA is the primary aneuploidy screening method and no NT is measured, 76801 is the correct code for the accompanying ultrasound.
• Documentation must reflect both services. If both are billed, the medical record must support both the NT measurement and the clinical rationale for ordering cfDNA.

Run a pre-submission payer policy check for any date of service carrying both 76813 and a cfDNA code. Building that check into the billing workflow costs far less than managing a post-payment recoupment.

Related CPT codes in the obstetric ultrasound family

CPT code 76813 sits within a family of obstetric ultrasound codes. Choosing the right code depends on gestational age, approach, level of detail, and whether the examination is a limited or comprehensive study. The AAPC CPT code lookup provides official descriptor text for each of the following codes.

When a first trimester scan requires both transabdominal and transvaginal approaches, 76813 covers the transabdominal portion. 76817 may then be billed separately for the transvaginal component, provided both approaches were medically necessary and documented. Do not substitute 76830 for 76817 on an obstetric claim.

An elevated nuchal translucency on the 76813 scan also prompts referral for fetal echocardiography. That study bills under 76825, usually performed between 18 and 24 weeks of gestation.

Later in the pregnancy, suspected growth restriction moves surveillance to umbilical artery Doppler. That scan carries its own code, 76820, reported once per fetus studied.

Common billing errors with CPT code 76813

Denied 76813 claims almost always trace back to one of five root causes. Each is preventable with front-end workflow controls rather than back-end appeals.

• Missing NT documentation. Billing 76813 without a documented NT value and saved NT image is the leading denial trigger. The report must state the NT measurement in millimeters, the imaging plane, and caliper placement. Build a documentation checklist into the ultrasound reporting template so the sonographer captures each element at the scan.
• Wrong gestational age. CPT code 76813 has a hard gestational age ceiling of 13 weeks 6 days. Scans performed at 14 weeks 0 days or later must use 76811 or another second-trimester code. EHR gestational age tracking should auto-flag encounters outside the billable range.
• Unbundling 76813 with 76801. Billing both 76813 and 76801 for the same gestation on the same date is an edit violation. Use only the more specific code that matches the services performed.
• Incorrect 76814 units. Billing 76814 x1 for a triplet pregnancy (which warrants x2) underbills and may cause reconciliation issues if the delivery record later shows three fetuses.
• ICD-10 mismatch. Using a second-trimester diagnosis code (e.g. O34 series) with 76813 will trigger a payer edit because the code is defined as first trimester only. Confirm the ICD-10 codes reflect the gestational age recorded at the visit.

A denial log sorted by code and payer surfaces the documentation deficiency behind repeated 76813 failures. Without that view, billing teams work each denial in isolation and never fix the template producing them.

How claims management software streamlines 76813 billing

First trimester ultrasound billing crosses the scan report, the eligibility check, and the claim file. When those records sit in separate systems, the NT value stays in the report and the claim goes out without support for it.

Pabau is practice management software that keeps the encounter, the documentation and the claim in one record. Pabau’s claims software for practices checks eligibility before the appointment, then submits the 76813 charge with its diagnosis code attached to the same visit.

Remittance data posts back automatically once the payer adjudicates, with the CARC denial reason recorded against the claim. Billing staff can see which 76813 claims were denied and why, without opening a separate payer portal.

Automate your obstetric billing workflows

Pabau helps OB/GYN and MFM practices track obstetric claims, catch incomplete documentation before submission, and reconcile remittance automatically. Clean claims go out on the first attempt.

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Conclusion

The payment on 76813 is fixed and predictable at about $115.57. What varies between practices is how much of it survives the payer’s review.

Capture the NT value, the CRL, the fetal heart rate and a saved NT image at the scan itself. Reconstructing any of them at appeal costs more staff time than the claim is worth, and it rarely works.

Get the unit count right on multiples, and check the payer’s antenatal screening policy before a cfDNA code shares the date. Book a demo to see how Pabau keeps obstetric ultrasound documentation and claim submission on one record.

Continue your research

Struggling with repeated obstetric claim denials? Denial management in healthcare covers how to build systematic workflows that surface root causes rather than treating each denial in isolation.

Need to understand how claims move from submission to payment? Revenue cycle management explained walks through the full billing lifecycle, from eligibility through remittance, for practice managers new to RCM.

Want to see how Pabau connects to a US medical claims clearinghouse? Claim.MD vs Office Ally compares the two most common clearinghouse options for OB/GYN and MFM billing teams.

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