ICD-10-CM 2027
ICD-10 code for level of literacy low
From the official ICD-10-CM alphabetic index entry “Low › level of literacy”. Page updated September 29, 2026.
About coding level of literacy low
The ICD-10-CM code for level of literacy low is Z55.0 (Illiteracy and low-level literacy).
Within Z55 (problems related to education and literacy), Z55.0 is specifically for Illiteracy and low-level literacy. Related codes cover Schooling unavailable and unattainable (Z55.1), failed school examinations (Z55.2), underachievement in school (Z55.3), educational maladjustment and discord with teachers and classmates (Z55.4), less than a high school diploma (Z55.5), problems related to health literacy (Z55.6), other problems related to education and literacy (Z55.8) and unspecified (Z55.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about level of literacy low ICD-10 codes
What is the ICD-10 code for level of literacy low?
- Z55.0 — Illiteracy and low-level literacy.
Is Z55.0 billable?
- Yes. Z55.0 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Z55.0 be used as a principal diagnosis?
- No. It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
Is Z55.0 a CC or MCC?
- No. Z55.0 is neither a CC nor an MCC under MS-DRG v44.0.