What is ICD-10 code E89.0?

E89.0 is the ICD-10-CM diagnosis code for Postprocedural hypothyroidism. Low thyroid hormone levels that develop after a surgical procedure or medical treatment affecting the thyroid gland. It belongs to the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89). E89.0 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. E89.0 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. E89.0 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. E89.0 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for E89.0?

E89.0 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards E89.0 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

What should coders know when reporting E89.0?

Always link this to the procedure that caused it; document whether it's temporary or permanent Distinguish from primary hypothyroidism by confirming the temporal relationship to the procedure

E89.0: Postprocedural hypothyroidism — ICD-10

ICD-10-CM Code View

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Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupE89.0Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Endocrine, nutritional and metabolic diseases (E00-E89) / Postprocedural endocrine and metabolic complications and disorders, not elsewhere classified (E89)

E89.0

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Postprocedural hypothyroidism

Low thyroid hormone levels that develop after a surgical procedure or medical treatment affecting the thyroid gland.

Buddy Insight

Postprocedural hypothyroidism occurs following thyroidectomy, radioactive iodine therapy, or external radiation therapy to the neck.

CMS-HCC V28

Not risk-adjusted for this model/period.

RAF 0

CMS-HCC V24

Not risk-adjusted for this model/period.

RAF 0

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Not risk-adjusted for this model/period.

RAF 0

RXHCC

Mapped

HCC 44

Thyroid and Parathyroid Disor...

RAF 0.0

Code Trumping

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Code Book Path

Official

E89Postprocedural endocrine and metabolic complications and disorders, not elsewhere classified

E89.0Postprocedural hypothyroidism

Inclusion Terms

Official

Postirradiation hypothyroidism
Postsurgical hypothyroidism

Excludes 2

Official

intraoperative complications of endocrine system organ or structure (E36.0-, E36.1-, E36.8)

Related Child Codes

Official

E89.1Postprocedural hypoinsulinemia

E89.2Postprocedural hypoparathyroidism

E89.3Postprocedural hypopituitarism

E89.4Postprocedural ovarian failure

E89.5Postprocedural testicular hypofunction

Includes

Official

ICD-10-CM does not list Includes notes for E89.0 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for E89.0 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for E89.0 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for E89.0 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for E89.0 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Diagnosis of hypothyroidism attributed to a prior procedure

Type of procedure that caused the hypothyroidism (thyroidectomy, radioactive iodine, radiation therapy)

Current thyroid function tests (TSH, free T4)

Levothyroxine dose and monitoring schedule

MEAT Support

HCC Buddy guidance

Diagnosis of hypothyroidism attributed to a prior procedure

Type of procedure that caused the hypothyroidism (thyroidectomy, radioactive iodine, radiation therapy)

Current thyroid function tests (TSH, free T4)

Levothyroxine dose and monitoring schedule

Audit Caution

HCC Buddy guidance

Using E03.9 (unspecified hypothyroidism) when documentation states hypothyroidism is post-surgical or post-radiation

Not reviewing surgical history to identify post-procedural etiology in hypothyroid patients

Assuming all hypothyroidism is autoimmune without checking for prior thyroid procedures

Missing this code in cancer survivors who received radioactive iodine or neck radiation

Common Mistakes

HCC Buddy guidance

E03.9 — Hypothyroidism, unspecified: use only when cause is unknown; E89.0 is required when post-procedural

E03.8 — Other specified hypothyroidism: for non-procedural specified causes

E06.3 — Autoimmune thyroiditis: Hashimoto thyroiditis, a different etiology

E89.1 — Postprocedural hypoinsulinemia: different endocrine gland affected by procedure

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is E89.0 an HCC code?

No. E89.0 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.

HCC Category Mapping

RxHCCHCC 44, Thyroid and Parathyroid Disorders

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for E89.0

For E89.0to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed E89.0 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

E89.0 is the ICD-10-CM diagnosis code for postprocedural hypothyroidism. Low thyroid hormone levels that develop after a surgical procedure or medical treatment affecting the thyroid gland. E89.0 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering postprocedural endocrine and metabolic complications and disorders, not elsewhere classified (e89).

E89.0 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This code does NOT map to a CMS-HCC under V24 or V28 models. It maps only to RxHCC 44. No direct RAF score impact for Medicare Advantage risk adjustment. Hypothyroidism in general does not carry HCC value regardless of etiology.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for E89.0 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Always link this to the procedure that caused it; document whether it's temporary or permanent
•Distinguish from primary hypothyroidism by confirming the temporal relationship to the procedure

Clinical Significance

Postprocedural hypothyroidism occurs following thyroidectomy, radioactive iodine therapy, or external radiation therapy to the neck. It is a permanent, iatrogenic condition requiring lifelong thyroid hormone replacement. While common and manageable, it must be accurately distinguished from autoimmune or other causes of hypothyroidism.

Documentation Requirements

✓Diagnosis of hypothyroidism attributed to a prior procedure
✓Type of procedure that caused the hypothyroidism (thyroidectomy, radioactive iodine, radiation therapy)
✓Current thyroid function tests (TSH, free T4)
✓Levothyroxine dose and monitoring schedule
✓Original indication for the thyroid procedure (cancer, Graves disease, goiter)

Commonly Confused Codes

•E03.9: Hypothyroidism, unspecified: use only when cause is unknown; E89.0 is required when post-procedural
•E03.8: Other specified hypothyroidism: for non-procedural specified causes
•E06.3: Autoimmune thyroiditis: Hashimoto thyroiditis, a different etiology
•E89.1: Postprocedural hypoinsulinemia: different endocrine gland affected by procedure