Is G40.00 a billable ICD-10-CM code?

No. G40.00 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does G40.00 sit in the tabular list?

Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).

What cannot be coded together with G40.00?

G40.00 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above G40.00 (G40.0, G40) and apply to it just the same.

G40.00

G40.00 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable

Non-billable headerICD-10-CM

G40.00 is a non-billable header ICD-10-CM code for localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, not intractable. It cannot be billed on its own: choose one of the more specific child codes below.

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 without intractability

Excludes1 inherited from the categories above G40.00

These are not written on G40.00, but they bind it: a note on a category applies to every code beneath it. Billing G40.00 with anything listed here is a denial.

Written on G40.0 — Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset

adult onset localization-related epilepsy (G40.1-, G40.2-)

Written on G40 — Epilepsy and recurrent seizures

conversion disorder with seizures (F44.5)
convulsions NOS (R56.9)
post traumatic seizures (R56.1)
seizure (convulsive) NOS (R56.9)
seizure of newborn (P90)

Excludes2 inherited from the categories above G40.00

Also inherited, and the opposite of Excludes1: these conditions are not part of G40.00, but a patient can have both, so you may code both.

Written on G40 — Epilepsy and recurrent seizures

hippocampal sclerosis (G93.81)
mesial temporal sclerosis (G93.81)
temporal sclerosis (G93.81)
Todd's paralysis (G83.84)

Other codes that can never be billed with G40.00

These codes carry an Excludes1 note pointing at G40.00. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading G40.00 alone.

G25.3Myoclonus
R56Convulsions, not elsewhere classified
R56.1Post traumatic seizures

Risk adjustment

G40.00 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code history

G40.00 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Code to one of these instead G40.00

2 child codes. Green means billable.

Related codes at this level

Codes that share G40.0. If G40.00 is not quite right, the correct code is usually one of these.

G40.01Localization-related (focal) (partial) idiopathic epilepsy and epileptic syndromes with seizures of localized onset, intractable

Questions about G40.00

Is G40.00 a billable ICD-10-CM code?: No. G40.00 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does G40.00 sit in the tabular list?: Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).
What cannot be coded together with G40.00?: G40.00 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above G40.00 (G40.0, G40) and apply to it just the same.