Billing codes · ICD-10-CM code

R73.03 prediabetes: billing nutrition therapy for prediabetes

By Javier Alvarez · Updated September 29, 2026 · 4 min read

Prediabetes referrals are some of the most useful visits a dietitian can see, and among the easiest to bill wrong. The code is simple. Coverage depends almost entirely on the payer, and Medicare works differently from everyone else.

R73.03 and its neighbors

R73.03 sits in subcategory R73.0, abnormal glucose, in the symptoms-and-findings chapter:

R73.0 codes carry Excludes1 notes, so they're never billed with:

• diabetes mellitus (E08-E13)
• gestational diabetes (O24.4-)
• abnormal glucose in pregnancy (O99.81-)
• dysmetabolic syndrome X (E88.81-)

For a pregnant patient with an abnormal glucose result, the code comes from Chapter 15, not R73.

Nothing in R73 changed in the FY2027 update (October 1, 2026).

Commercial coverage: preventive vs. medical

Prediabetes is where preventive nutrition benefits pay most clearly.

The USPSTF basis. The 2021 USPSTF recommendation (grade B) covers screening adults aged 35 to 70 who have overweight or obesity. It also says clinicians should offer or refer patients with prediabetes to effective preventive interventions. Under the ACA, non-grandfathered plans cover USPSTF A and B services without cost-sharing.

How one payer turns that into codes. UnitedHealthcare's Preventive Care Services policy (MP.016.59, effective July 1, 2026) has a Pre-Diabetes Preventive Interventions row:

• Procedure codes include MNT (97802, 97803, 97804, G0270, G0271), preventive counseling 99401-99404, and several behavioral counseling codes.
• It requires diagnosis code R73.03.
• It's limited to ages 35 to 70 (ending on the 71st birthday).

For a UHC commercial member in that age range, R73.03 is the code that routes MNT to the preventive benefit. Z71.3 doesn't do that job in this row. A 30-year-old with prediabetes falls outside the row, and the visit is judged under the medical benefit.

Other payers. Aetna's CPB 0049 treats counseling as preventive for adults who are overweight with cardiovascular risk factors, and impaired fasting glucose (R73.01) is one of them. Cigna's preventive policy uses its own designated wellness code list. Every plan draws the line somewhere different, so check the member's benefit before the first visit.

Medicare: MNT doesn't cover prediabetes

Medicare Part B covers MNT only for beneficiaries with diabetes or renal disease, on referral from a physician (42 CFR 410.130-410.132 and NCD 180.1). Prediabetes isn't diabetes: the R73 category excludes E08-E13. A Medicare MNT claim with R73.03 should be expected to deny.

Medicare's program for prediabetes is the Medicare Diabetes Prevention Program (MDPP), a structured lifestyle program. MDPP services are billed by organizations enrolled as MDPP suppliers, under their own rules and codes, not through 97802/97803. If you want to serve Medicare patients with prediabetes, look at MDPP supplier enrollment. If the patient later receives a diabetes diagnosis, MNT on E11.x becomes available with a referral. The Medicare MNT guide covers the referral and hours.

Medicare Advantage plans can offer extra benefits beyond Original Medicare. Check the specific plan.

Pairing R73.03 with 97802/97803 and Z71.3

The CPT code follows the visit: 97802 for the initial assessment, 97803 for follow-ups, each 15-minute unit counted by the time face to face. Z71.3's role in all this is on the Z71.3 page.

Documentation that supports R73.03

• The provider's diagnosis of prediabetes, from the referral or chart. You code from the provider's documentation; a lab value in your note isn't enough to assign R73.03 yourself.
• The lab that supports it, if available (A1c, fasting glucose or OGTT, with date), since some payers ask for it on records review.
• Age and, for preventive routing, the date of birth on the claim matching the member's record, because age limits are enforced automatically.
• Your assessment, intervention and goals, with time face to face.

Denials and fixes

The payer-by-payer logic behind these is covered in preventive vs. medical benefits and the Z71.3 denials guide.

For the other diagnosis codes on nutrition claims, see the ICD-10 codes for dietitians reference.