Gunshot wounds are typically treated in acute care settings, but longer-term sequelae are likely treated by ambulatory care providers. To understand whether gunshot wounds treated in acute care settings are later documented in ambulatory care electronic health records, acute care claims and ambulatory care electronic health records data were linked. The primary objective was to determine the percentage of patients with a gunshot wound diagnosis in their ambulatory care electronic health records from all patients with both an acute care gunshot wound diagnosis and an observed follow-up ambulatory care visit. The second objective was to identify demographic and clinical factors associated with a patient having a gunshot wound diagnosis in their ambulatory care electronic health records. This observational study linked Oregon Medicaid claims for acute gunshot wound with ambulatory care electronic health records in OCHIN's ADVANCE Data Warehouse from 2012 to 2022 for case identification. Patients with and without an International Classification of Diseases code for gunshot wound in their ambulatory care electronic health records were characterized using descriptive statistics. Multivariable logistic regression conducted between 2024 and 2025 modeled predictors of gunshot wound diagnosis in follow-up ambulatory care electronic health records controlling for patient characteristics. Only 34.3% of patients with a gunshot wound event treated in an acute setting and with an observed ambulatory care visit had a gunshot wound diagnosis in their ambulatory care electronic health records. Time between acute gunshot wound and follow-up ambulatory care and the severity of the acute gunshot wound injury were associated with having a gunshot wound ambulatory care electronic health records diagnosis. Patients identified as Black, non-Hispanic or Hispanic had higher odds of having a gunshot wound ambulatory care electronic health records diagnosis than those identified as White, non-Hispanic. Most people who had a gunshot wound treated in an acute care setting with a later ambulatory care visit did not have a gunshot wound diagnosis in their ambulatory care electronic health records, even though a gunshot wound event can be relevant history for ambulatory care providers and patient care. Strategies to document prior gunshot wound in ambulatory electronic health records should be developed to support whole-person care in ambulatory settings.