ICD-10 Code G40.1 – Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G40.1 – Localization-related (focal) (partial) symptomatic epilepsy and epileptic syndromes with simple partial seizures
What it is
This code identifies focal symptomatic epilepsy in which seizures remain simple partial, meaning awareness is preserved and the seizure starts in one area of the brain. It is used when the record specifies this seizure type.
Clinical signs
Typical findings include focal motor, sensory, autonomic, or psychic symptoms without loss of consciousness. Clinical features vary; refer to documentation for the exact seizure description and whether the epilepsy is symptomatic.
When to use this code
Use G40.1 when the provider documents localization-related epilepsy or epileptic syndrome with simple partial seizures. Apply it when the chart supports focal onset and preserved awareness, and the episode is not described as generalized, complex partial, or another seizure type.
Do not use for
Do not use this code if the seizure type is generalized, complex partial, or unspecified. Check documentation if the record does not clearly state simple partial seizures or if the epilepsy classification is missing.
Coding tip
Match the code to the provider’s exact seizure terminology and confirm focal onset with preserved awareness before assigning G40.1.