While Z codes in ICD-10-CM may not receive much attention, they hold immense value in supporting patients’ overall health. Learn why in this Z codes 101 guide.
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What are Z codes in ICD-10-CM?
Z codes, which belong to a standardized classification system of diagnosis codes called ICD-10-CM, capture factors influencing a patient’s health status or reasons for utilizing health services that are not classifiable elsewhere as diseases, injuries, or external causes. In short, Z codes help to illustrate a patient’s comprehensive health profile and the various factors driving their healthcare needs.
Healthcare professionals can find these codes in Chapter 21: Factors influencing health status and contact with Health Services (Z00-Z99) of the ICD-10-CM coding system.
Why is it important to capture Z codes?
Z codes contribute to a comprehensive understanding of a patient’s health by connecting non-disease factors that influence an individual’s well-being. What sets these codes apart is their ability to capture a wide range of factors important to overall health that do not necessarily indicate a specific disease state. Some of the codes may be reported by various members of the care team, including case managers or social workers.
At an individual patient level, Z codes are invaluable for clinicians, aiding in the development of personalized treatment plans and preventative care strategies. Additionally, they can be used for population analytics, providing additional context to better identify factors that increase healthcare utilization and costs.
What type of information do Z codes capture?
Z codes identify a range of issues related, but not limited to, preventative health services, education, literacy, employment, housing, the ability to obtain adequate amounts of food, occupational exposure to toxic agents, body mass index ranges for all age patients, long term use of drug therapies, and more.
How are Z codes categorized?
Are Z codes reimbursable?
Until recently, Z codes minimally affected reimbursement models. However, as of 2024, the Centers for Medicare & Medicaid Services (CMS) requires hospitals that accept Medicare payments to screen all inpatients aged 18+ for Social Determinants of Health (SDOH) as part of the Hospital Inpatient Quality Reporting program.
Ambulatory providers also have the option to take advantage of additional Medicare incentives for capturing SDOH. These determinants are primarily captured using ICD-10-CM codes from Z55-Z65. While SDOH Z codes were previously underutilized, there is growing recognition of their value to clinicians, researchers, public health agencies, and more. This is prompting changes in the reimbursement landscape regarding Z code captures.
How will Z codes help capture SDOH?
SDOH represents environmental conditions where people are born, live, learn, work, play, worship, and age that affect a wide range of health, function, and quality-of-life outcomes and risks. The World Health Organization (WHO) estimates that these social factors account for 30-55% of health outcomes.
Anyone in the care team can collect SDOH codes by using a screening tool that captures multiple factors of ICD-10-CM codes Z55-Z65. CMS and other federal programs can leverage these insights to inform value-based care opportunities and advocate for updating and creating new policies. This can help address health disparities, identify community needs, support quality measurements, and improve overall health outcomes.
How can Z codes provide value to both payers and providers?
For providers, Z codes focused on Social Determinants of Health provide an industry standard way to communicate conditions typically ‘lost’ in free text, enabling a more holistic view of patient health and supporting personalized treatment and downstream processes. This level of granularity in documentation can also help providers identify at-risk populations and allocate resources more effectively, improving patient outcomes.
For payers, Z codes can increase the incentive to invest financial support for SDOH concerns and promote care that better addresses SDOH factors. Ultimately, increased utilization of Z codes can facilitate collaboration between providers and payers, supporting population health management initiatives and proactive care strategies.
How do Z codes benefit value-based care initiatives?
Healthcare organizations are increasingly focused on improving health outcomes while minimizing costs and frequent visits. To that end, documenting accurately is essential. Z codes help providers close critical care gaps by recording and addressing key social risks, such as lack of reliable transportation or job insecurity.
A relevant example is the Z code for sepsis after care, introduced in 2025 to represent situations where patients are receiving after care for ‘sepsis’ but are not in the acute phase of sepsis. This code underscores the importance of accurate clinical documentation and how it can help tell the patient story.
By leveraging Z codes, clinicians can go beyond the individual patient to support the collection of actionable insights, accelerating value-based care initiatives and driving improvements in health equity. To achieve this, provider organizations should regularly audit and optimize their SDOH documentation with the help of a trusted partner.
2025 Z code updates
Several new and revised Z codes have been introduced to the ICD-10-CM code set this year. Here are some of the key updates:
Z codes for Breast Cancer Diagnoses: New Z codes have been added to indicate the progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) status, which are to be used in conjunction with breast cancer diagnoses.
Z codes for Genetic Susceptibility: New Z codes include those for genetic susceptibility to epilepsy and neurodevelopmental disorders (Z15.1) and genetic susceptibility to obesity (Z15.2).
Z codes for Receptor Status: Codes specific to progesterone receptor status (Z17.2-) and human epidermal growth factor receptor status (Z17.3-) have been added.
Z code for Sepsis After Care: A new Z code for encounter for sepsis after care has been introduced.
