Documentation

Altair Documentation

Browse our medical billing knowledge base — denial codes, payer-specific guides, billing modifiers, regulatory requirements, clinical specialty rules, and state laws.

CARC denial code reference — what each code means, why it happens, and how to resolve it.

Medical billing terminology — clear definitions for the terms billing teams encounter daily.

Billing Modifiers

CPT modifier usage rules, documentation requirements, and payer acceptance guidelines.

Payer-specific billing guides — coverage policies, authorization timelines, appeals, and denial patterns.

Healthcare regulatory requirements — compliance rules, deadlines, and how to stay compliant.

Clinical Specialties

Specialty-specific coding and billing rules for behavioral health, cardiology, dermatology, and more.

State Billing Laws

State-by-state filing deadlines, balance billing rules, surprise billing protections, and prior auth requirements.