Medi-Cal directs DRG resubmissions after the October 1 Mapper 44.0 change
Oct 18, 2026 edition · GC-2026-0421 · Published 2026-10-18 · Version 1 · Announced
DHCS’s October 15 notice addresses claims affected by the October 1 DRG Mapper update. It identifies three denial codes for resubmission, calls for present-on-admission indicators and describes a separate erroneous-payment correction for eligible claims reimbursed incorrectly during system implementation.
What happened
DHCS announced on October 15 that the Medi-Cal DRG program had updated the Solventum Mapper to version 44.0 for service dates on or after October 1, 2026, incorporating new ICD-10-CM and ICD-10-PCS codes. It warns that claims using new codes for admissions on or after October 1 could have been denied if the payment-system update was incomplete when the claim was submitted. The notice identifies RAD 67 for an unmatched primary/secondary surgical procedure, 9124 for a missing or invalid diagnosis and 9962 when a valid APR-DRG could not be determined, and instructs providers receiving one of these denials to resubmit.
The notice also says present-on-admission indicators should be included to prevent adjudication delays. It describes an Erroneous Payment Correction to reprocess claims with service dates on or after the billing-policy effective date that were appropriately submitted under the article’s guidance but reimbursed incorrectly before the system changes were implemented. Providers may alternatively correct and resubmit previous claims under the manual’s CIF Submission and Timeliness Instructions. The announced correction concerns erroneous reimbursement; it should not replace the separate instruction to resubmit the listed denials.
Scope and timing
- Authority status
- Announced
- Applicability
- Operationally relevant
- Audience
- Health systems, Provider networks
- Jurisdiction
- California
- Affected functions
- Revenue Cycle, Coding
- Responsible owner
- Revenue Cycle
Why it matters
Denial follow-up and erroneous-payment correction describe different affected populations. A blanket expectation that every denied claim will be corrected automatically could delay appropriate resubmission.
Recommended action
Suggested internal action: Revenue Cycle should identify relevant post-October 1 admissions with the three listed RAD codes, assess resubmission under the notice and applicable timeliness instructions, check POA data, and separately monitor the announced correction for appropriately submitted claims reimbursed incorrectly. Do not invent a correction-run date.
Implementation playbook
- Separate listed-denial resubmission work from erroneous-reimbursement monitoring; suggested internal review. Revenue Cycle
- Check new code validity and POA data for affected admissions; suggested internal review. Coding
Sources
- DRG Payment System Update to Mapper Version 44.0 on October 1, 2026Official · DHCS / Medi-Cal Providers · 2026-10-15
Complete edition and supplemental material
This finding in the complete approved report →Regulatory horizons, CIA trends and implementation trackers remain in the full report.
Read the entire Medicare & Medicaid report →