Bariatric surgery prior authorization and NCD 100.1 checklist.
Bariatric surgery is the one general surgery procedure family where prior authorization runs on documentation, not just an authorization number. NCD 100.1 sets three conditions that must all be met before Medicare covers gastric bypass, biliopancreatic diversion with duodenal switch, or adjustable gastric banding, and two items practices still check — facility center-of-excellence certification and blanket sleeve gastrectomy coverage — stopped being accurate years ago. This is the code-level checklist to build scheduling and pre-bill review around.
Key takeaways
- NCD 100.1 requires all three conditions, not two of three: BMI ≥35, at least one documented obesity-related comorbidity, and documented failed prior medical treatment for obesity.
- Facility center-of-excellence certification was dropped in 2013. A checklist still asking for it is filtering out cases Medicare no longer gates that way.
- Stand-alone laparoscopic sleeve gastrectomy is MAC discretion, not a national guarantee — Novitas, WPS, and Noridian each publish their own bariatric billing article; coverage isn't automatic just because RYGBP is covered nationally.
- Six specific procedures are nationally non-covered regardless of documentation — no amount of BMI, comorbidity, or failed-treatment charting changes that.
Why this prior auth runs on the chart, not the authorization number
Most general surgery prior authorization is a utilization-management question: does this payer require sign-off before this CPT code, and did staff get it. Bariatric surgery adds a harder layer underneath — even with an authorization number in hand, the claim itself has to demonstrate that NCD 100.1 (Bariatric Surgery for Treatment of Co-Morbid Conditions Related to Morbid Obesity), confirmed directly against the CMS Coverage Database, was actually met on the date of service. A CO-50 medical necessity denial on a bariatric claim is rarely about the wrong CPT code; it's almost always one of the three conditions below being present somewhere in the chart but never stated in a form that supports the specific ICD-10 code billed.
The three conditions, and the chart language that actually satisfies each one
NCD 100.1 covers open and laparoscopic Roux-en-Y gastric bypass (RYGBP), open and laparoscopic biliopancreatic diversion with duodenal switch (BPD/DS), and laparoscopic adjustable gastric banding (LAGB) only when all three conditions below are met.
- 1Body-mass index of 35 kg/m² or greater. The chart needs recorded height and weight the BMI is calculated from, not a stated BMI number with no source data behind it — report the specific Z68 band (see the ICD-10 table below) alongside the qualifying obesity diagnosis.
- 2At least one obesity-related comorbidity, explicitly linked to the obesity in the note. Type 2 diabetes (E11.9 and its complicated variants) has qualified since February 12, 2009; hypertension (I10) and obstructive sleep apnea (G47.33) are also commonly qualifying. A comorbidity listed elsewhere on the problem list without a documented connection is a weaker claim than one the note ties directly to it.
- 3Documented, unsuccessful prior medical treatment for obesity. The record has to show what was tried — a structured diet, pharmacotherapy, a supervised weight-management program — and that it didn't work. “Patient has tried to lose weight” without specifics is the most common reason this condition fails on chart review.
One exception carves BMI below 35 out entirely, regardless of comorbidity: effective February 12, 2009, CMS determined RYGBP, LAGB, and BPD/DS are not covered for beneficiaries with type 2 diabetes and a BMI under 35 — a diabetes diagnosis alone never substitutes for the BMI threshold.
Procedure-by-procedure coverage status
Not every bariatric CPT code sits under the same rule. Codes below are paraphrased, not reproduced verbatim from the CPT Professional edition; coverage status is confirmed against NCD 100.1.
| Code | Procedure | Coverage status |
|---|---|---|
43644 | Laparoscopic RYGB, short limb | Nationally covered when all three conditions are met |
43645 | Laparoscopic RYGB with small intestine reconstruction (malabsorptive) | Nationally covered when all three conditions are met |
43846 | Open RYGB, short limb | Nationally covered when all three conditions are met |
43847 | Open RYGB with small intestine reconstruction | Nationally covered when all three conditions are met |
43845 | Open biliopancreatic diversion with duodenal switch | Nationally covered when all three conditions are met |
43659 | Unlisted laparoscopic procedure, stomach — used for laparoscopic BPD/DS, which has no dedicated CPT code | Covered when the three conditions are met; requires a comparison code and operative report on the claim |
43770–43774 | Laparoscopic adjustable gastric band placement, adjustment, removal, and replacement family | Nationally covered when all three conditions are met; revision/removal follows medical necessity, not the original criteria a second time |
43775 | Laparoscopic sleeve gastrectomy, stand-alone | MAC discretion, not national — same three conditions, decided locally |
43848 | Revision of open gastric restrictive procedure | Covered when the revision itself is medically necessary |
| — | Open adjustable gastric banding; open sleeve gastrectomy; open and laparoscopic vertical banded gastroplasty; intestinal bypass surgery; gastric balloon | Nationally non-covered for all Medicare beneficiaries, regardless of documentation |
The 2026 CPT set added 43889, transoral endoscopic suturing to reduce stomach volume — an incision-free option positioned for a BMI of 30 or greater plus a related comorbidity. It sits outside NCD 100.1 entirely, and several payers hadn't published a formal policy for it as of this build. ⚠️ Treat a prior-auth request for it as headed for exception review this year, not an automated pathway.
ICD-10 codes that document the claim
Confirmed live against the FY2026 ICD-10-CM code set via the ICD-10 coverage connector.
| Code | BMI range (adult) |
|---|---|
Z68.35–Z68.39 | 35.0–39.9 |
Z68.41 | 40.0–44.9 |
Z68.42 | 45.0–49.9 |
Z68.43 | 50.0–59.9 |
Z68.44 | 60.0–69.9 |
Z68.45 | 70 or greater |
Pair the Z68 band with the underlying obesity diagnosis — E66.01 (morbid obesity due to excess calories), E66.09 (other obesity due to excess calories), E66.2 (morbid obesity with alveolar hypoventilation), or E66.813 (obesity, class 3) are all confirmed billable codes carrying the clinical picture the Z68 code alone doesn't. On the comorbidity side, E11.9 (type 2 diabetes), I10 (essential hypertension), and G47.33 (obstructive sleep apnea) are the three most commonly qualifying codes, all confirmed valid for HIPAA transactions.
Novitas's A56422 and WPS's A54923 both took effect 01/01/2026, and Noridian retired its prior article (A53028) on 09/25/2025 in favor of a new one (A53026). Pull the current version from the CMS Coverage Database, not a saved PDF from a prior benefit year.
MAC-specific billing articles behind the NCD
NCD 100.1 is national, but the claim-completion detail underneath it is published per MAC, the same pattern general surgery's wound care and colonoscopy coverage follows. Confirmed live against the CMS Coverage Database.
| Document | Title | MAC | Effective date |
|---|---|---|---|
L35022 | Bariatric Surgical Management of Morbid Obesity (LCD) | Novitas Solutions, Inc. | 05/13/2021 |
A56422 | Billing and Coding: Bariatric Surgical Management of Morbid Obesity | Novitas Solutions, Inc. | 01/01/2026 |
A54923 | Billing and Coding: Bariatric Surgery for Treatment of Co-Morbidities Conditions Related to Morbid Obesity | WPS Insurance Corporation | 01/01/2026 |
A53026 | Billing and Coding: Bariatric Surgery Coverage | Noridian Healthcare Solutions, LLC | 01/01/2026 |
⚠️ Document IDs, MAC names, and effective dates above were retrieved live from the CMS Coverage Database and confirmed active as of this build; the covered-diagnosis lists and claim-completion detail inside each article were not independently re-verified here (CMS's article detail pages blocked automated retrieval during this build), so pull the specific article text for your own MAC before finalizing a checklist against it. If your MAC isn't one of the three above, search the CMS Coverage Database for your own jurisdiction's bariatric article first.
Do and don't
- Confirm the chart shows recorded height and weight the BMI is calculated from, not just a stated figure.
- Document the qualifying comorbidity as explicitly linked to the obesity, not just present on the problem list.
- Spell out what conservative treatment was tried, for how long, and why it fell short.
- Check your MAC's current stand-alone sleeve gastrectomy stance before scheduling one.
- Cite NCD 100.1 and the MAC's billing article by number in the first paragraph of any CO-50 appeal.
- Don't ask for center-of-excellence certification on a Medicare claim — CMS dropped it for dates of service on and after September 24, 2013.
- Don't assume laparoscopic sleeve gastrectomy is covered nationally the way RYGBP is; it's MAC discretion.
- Don't submit a claim for open AGB, open sleeve gastrectomy, vertical banded gastroplasty, intestinal bypass, or a gastric balloon — all nationally non-covered regardless of documentation.
- Don't rely on a type 2 diabetes diagnosis alone to clear the comorbidity condition if BMI is under 35 — that combination was excluded from coverage in 2009.
Bariatric prior auths stalling or denying at your practice?
We'll review your intake checklist against NCD 100.1 and your MAC's current billing article, and flag where documentation is falling short before the claim goes out.
Frequently asked questions
Does Medicare still require facility certification for bariatric surgery centers?
No. Facility certification as an American College of Surgeons Level 1 Bariatric Surgery Center or an American Society for Bariatric Surgery Center of Excellence was required through September 23, 2013, and CMS removed that requirement for dates of service on and after September 24, 2013. A prior-auth checklist still asking for a center-of-excellence attestation on a Medicare claim is asking for something that hasn't been required in over a decade.
Is laparoscopic sleeve gastrectomy covered by Medicare?
Not as a national coverage guarantee the way gastric bypass, biliopancreatic diversion with duodenal switch, and adjustable gastric banding are. Effective June 27, 2012, CMS left coverage of stand-alone laparoscopic sleeve gastrectomy to each Medicare Administrative Contractor's discretion, conditioned on the same three criteria as the nationally covered procedures: BMI of 35 kg/m² or greater, at least one obesity-related comorbidity, and documented unsuccessful prior medical treatment for obesity. Confirm your specific MAC's current position — Novitas, WPS, and Noridian each publish their own bariatric billing article — before assuming it's covered the same way gastric bypass is.
What ICD-10 codes document BMI for a bariatric surgery prior authorization?
The Z68 category reports BMI in whole-point bands: Z68.35 for BMI 35.0–35.9, Z68.36 through Z68.39 up to 39.9, Z68.41 for 40.0–44.9, Z68.42 for 45.0–49.9, Z68.43 for 50.0–59.9, Z68.44 for 60.0–69.9, and Z68.45 for 70 or greater — all confirmed billable, HIPAA-valid codes in the FY2026 ICD-10-CM set. Report the band the chart's recorded height and weight actually calculate to, alongside a qualifying obesity diagnosis such as morbid obesity due to excess calories (E66.01) or obesity, class 3 (E66.813) — the Z68 code documents the number NCD 100.1's BMI threshold turns on, but it doesn't substitute for the obesity diagnosis code itself.
Verify before billing. CPT is a registered trademark of the American Medical Association; codes here are paraphrased, not reproduced from the CPT Professional edition. CPT, HCPCS and ICD-10 codes, coverage policy, and bundling edits change, including annual code-set updates. This page reflects standard industry practice and is provided for general education — it is not a substitute for your own compliance review, your current payer contracts, or the current-year code sets. Confirm requirements against your specific payer mix before submitting claims.