Blue Shield of California
California Physicians' Service d/b/a Blue Shield of California · Blue Shield of California (independent BCBSA licensee) · NAIC 47228
Where to send the appeal
Verified addresses and inbound channels. We refresh on every release.
Response timeline
The clocks that matter. Miss them and you escalate to the state insurance commissioner.
Codes worth fighting
Based on outcome data across our payer corpus.
- CO-97
- CO-18
- CO-167
- CO-204
- CO-4
- CO-50
- CO-29
Modifier behavior
The denials this payer applies on modifier-bearing claims. The rebuttal language is part of the Denial OS letter generator and not published here.
Modifier 59
Distinct Procedural ServiceBlue Shield CA's edits engine bundles 97140 + 97110 same day; modifier 59 required and frequently challenged.
Modifier 25
Significant, Separately Identifiable E/M ServiceStandard CO-97 / CO-4 denial pattern when modifier missing; less aggressive than Anthem on documentation threshold.
Interest statute
The legal basis for charging interest when payment runs late.
California Health & Safety Code §1371.35 (HMO claim resolution, 15% interest on Knox-Keene claims after 45 days) AND California Insurance Code §10123.13 (PPO products)
Knox-Keene Act applies (CA HMOs regulated by DMHC).
You have the playbook. Now write the letter.
Paste your EOB and Denial OS generates the appeal in five minutes — citing the contracted rate, the modifier rebuttal, and the deadline statute that matches this exact payer.
Start your appeal