MCMCB Pro
G40.009

G40.009Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus

Billable / specific codeICD-10-CM

G40.009 is a billable, specific ICD-10-CM code for localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable, without status epilepticus. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset NOS

Risk adjustment

G40.009 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:

  • HCC 201 Seizure Disorders and Convulsions0.245 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.

Medicare coverage

G40.009 is named in 17 Medicare coverage policies 17 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A56551Billing and Coding: Visual Fields Testing
  • A56612Billing and Coding: CT of the Head
  • A56619Billing and Coding: Nerve Conduction Studies and Electromyography
  • A56631Billing and Coding: Thoracic Aortography and Carotid, Vertebral, and Subclavian Angiography

How G40.009 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to G40.009.

  • Epilepsy, epileptic, epilepsialocalization-relatedidiopathic
  • Epilepsy, epileptic, epilepsialocalization-relatedidiopathicwith seizures of localized onset
  • Epilepsy, epileptic, epilepsiasyndromeslocalization-relatedidiopathic
  • Epilepsy, epileptic, epilepsialocalization-relatedidiopathicwith seizures of localized onsetnot intractable
  • Epilepsy, epileptic, epilepsiasyndromeslocalization-relatedidiopathicwith seizures of localized onset
  • Epilepsy, epileptic, epilepsialocalization-relatedidiopathicwith seizures of localized onsetnot intractablewithout status epilepticus
  • Epilepsy, epileptic, epilepsiasyndromeslocalization-relatedidiopathicwith seizures of localized onsetnot intractable
  • Epilepsy, epileptic, epilepsiasyndromeslocalization-relatedidiopathicwith seizures of localized onsetnot intractablewithout status epilepticus

Related codes at this level

Codes that share G40.00. If G40.009 is not quite right, the correct code is usually one of these.

Questions about G40.009

Is G40.009 a billable ICD-10-CM code?
Yes. G40.009 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does G40.009 sit in the tabular list?
Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.