Key facts for DRG 964
- FY2027 relative weight
- 1.4970
- Higher than 43% of all MS-DRGs
- Change vs FY2026
- -2.4%
- FY2026 weight 1.5330
- Geometric mean LOS
- 3.8 days
- Arithmetic mean 4.8 days
- MDC
- 24
- 24
- Severity level
- with CC (complication or comorbidity)
- Transfer policy
- Not a transfer DRG
TL;DR
MS-DRG 964 is a medical group in MDC 24 (24) at the middle severity level of its family. CMS assigns it a FY2027 relative weight of 1.4970 with a geometric mean length of stay of 3.8 days and an arithmetic mean of 4.8. Its weight moved down 2.4% from FY2026 (1.5330). That weight is higher than 43% of all medical and surgical MS-DRGs. Its CC/MCC family (DRG 963, DRG 965) spans weights 1.0050 to 2.6360.
What changed from FY2026 to FY2027
CMS recalibrates every MS-DRG weight annually from the prior year's MedPAR claims. For DRG 964 the FY2027 relative weight is 1.4970 against 1.5330 in FY2026, a fall of 2.35%, which exceeds the 2% threshold worth re-checking in contract models.
| Metric | FY2026 | FY2027 | Change |
|---|---|---|---|
| Relative weight | 1.5330 | 1.4970 | -0.0360 |
| Geometric mean LOS (days) | 3.9 | 3.8 | -0.1 |
| Arithmetic mean LOS (days) | 4.9 | 4.8 | -0.1 |
CC and MCC family
DRG 964 shares its base definition with 2 other MS-DRGs split by severity. The family's weights span 1.0050 to 2.6360, a 2.62× spread, which is the payment effect of documenting qualifying complications and comorbidities.
Grouper logic (v44 Definitions Manual)
The Definitions Manual assigns DRG 964 through the MDC 24 principal-diagnosis table and the absence of a qualifying operating-room procedure rather than a DRG-specific code list. See the manual chapter for MDC 24.
Documentation and denial exposure
As a medical DRG, assignment depends on the principal diagnosis sequenced from the attending's documentation; a secondary condition sequenced first, or a symptom code in place of the confirmed diagnosis, changes the MDC or the DRG. Because this family splits by severity, auditors target CC and MCC capture: each secondary diagnosis must be documented as present, monitored, evaluated or treated during the stay to survive a DRG-validation review. Typical inpatient denial codes for this group: CARC 16 (claim lacks information needed to group the stay), CARC 50 (the admission or procedure is judged not medically necessary), CARC 97 (a service is bundled into the DRG payment).
How QuickIntell uses DRG 964 data
QuickCode groups inpatient encounters against the current v44 logic, flags CC and MCC candidates that lack supporting documentation, and shows the weight difference across the family before the claim drops. QuickScribe captures the attending's language that supports severity, and QuickRCM works DRG-validation denials with the grouper evidence attached.
Frequently asked questions — DRG 964
What is MS-DRG 964?
MS-DRG 964 is "Other Multiple Significant Trauma with CC", a medical Medicare Severity Diagnosis-Related Group in MDC 24, 24. Medicare pays inpatient stays grouped here at the hospital's base rate multiplied by the DRG relative weight.
What is the FY2027 relative weight for DRG 964?
The FY2027 relative weight is 1.4970 (IPPS final rule Table 5, effective October 1, 2026). In FY2026 it was 1.5330, a change of -2.4%.
What is the average length of stay for DRG 964?
CMS reports a geometric mean length of stay of 3.8 days and an arithmetic mean of 4.8 days for FY2027. The geometric mean is used for transfer-payment calculations.
Which DRGs are in the same CC/MCC family as 964?
DRG 963 (Other Multiple Significant Trauma with MCC, weight 2.6360); DRG 965 (Other Multiple Significant Trauma without CC/MCC, weight 1.0050). The family's weights range from 1.0050 to 2.6360, so documented complications and comorbidities change payment materially.
What documentation supports the severity level of DRG 964?
DRG 964 is reached when the stay carries a secondary diagnosis from the CMS Complication or Comorbidity list but none from the MCC list. Common CC captures include chronic kidney disease stage 3 and above, uncontrolled diabetes with manifestations, malnutrition of specified severity and heart failure of a stated type. Each must be documented by the treating clinician and show clinical relevance in the record; a condition listed only in the problem list without assessment is the most frequent reason a CC is removed on audit and the stay drops to the base DRG.
Is DRG 964 a post-acute transfer DRG?
No. DRG 964 is not on the FY2027 post-acute care transfer list, so the transfer per-diem policy does not apply to it.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-01. Verify against the primary file before billing or contracting decisions.
- IPPS FY2027 Final Rule Table 5 (CMS-1849-F)Version v44 FY2027 · effective 2026-10-01 · file CMS-1849-F Table 5.txtSHA-256 01003dd571c1e2f5…
- IPPS FY2026 Final Rule Table 5 (CMS-1833-F)Version v43 FY2026 · effective 2025-10-01 · file CMS-1833-F Table 5.txtSHA-256 bf8c390d14b3cd3e…
- ICD-10 MS-DRG Definitions Manual v44 (text)Version v44 · effective 2026-10-01 · file fy2027-fr-icd10-ms-drg-definitions-manual-files-v44.zipSHA-256 ae4f6c11727fe91f…
Disclaimer
This page is an operational reference compiled from the CMS IPPS FY2027 final rule (Table 5) and the v44 ICD-10 MS-DRG Definitions Manual. Relative weights are national factors; actual payment depends on each hospital's wage-adjusted base rate, add-ons, outliers and transfer adjustments. Nothing here is legal, clinical or billing advice; verify grouping against your encoder and the published CMS files.