Knowledge Network
The open directory of healthcare billing rules, payer policies, facility data, and coding references. Search, browse, and use — free.
Payer Rules
3,400+ payers
Filing deadlines, appeal levels, prior auth requirements, and policy details for 3,400+ payers.
Medicare
12-month filing, 5 appeal levels, 120-day redetermination
UnitedHealthcare
90-day filing (commercial), 180-day appeal window
Aetna
180-day filing, independent review available
Blue Cross Blue Shield
Varies by plan — 60–365 day filing windows
Facility Directory
200K+ facilities
CCN-resolved facility data. Location, type, payment system, billing form, and care setting for every Medicare-enrolled provider.
CCN 170001
Kansas • Short-term Hospital • MPFS • CMS-1500
CCN 050454
California • Short-term Hospital • OPPS • UB-04
CCN 335412
New York • SNF • SNF PPS • UB-04
CCN 457300
Texas • Home Health • HH PPS • UB-04
Billing Rules
10K+ rules
TOB codes, POS codes, modifiers, revenue codes, NCCI edits, and billing form requirements — all cross-referenced.
TOB 0131
Hospital Outpatient • Outpatient services at hospital
POS 22
On-campus outpatient hospital • Facility rate
Modifier 25
Significant, separately identifiable E/M • Allows separate payment
NCCI 99213/36415
Modifier indicator 1 • Can unbundle with modifier
Payment Data
89 MAC localities
GPCI values, RVU tables, conversion factors, and fee schedule data by geography and facility type.
Manhattan, NY
Work GPCI 1.058 • PE GPCI 1.281 • MP GPCI 1.385
Rest of Kansas
Work GPCI 1.000 • PE GPCI 0.886 • MP GPCI 0.411
San Francisco, CA
Work GPCI 1.068 • PE GPCI 1.544 • MP GPCI 0.628
Rest of Texas
Work GPCI 1.000 • PE GPCI 0.869 • MP GPCI 0.895
Denial Codes
350+ CARC/RARC codes
CARC and RARC code directory with plain-English explanations, root cause categories, and recommended resolution strategies.
CARC 197
Precertification/authorization absent • Request retro auth
CARC 50
Non-covered service • Validate medical necessity
CARC 29
Time limit for filing expired • Check exceptions
CARC 16
Missing/incomplete information • Identify missing fields
Rule Change Feed
Daily updates
Real-time feed of payer rule changes, CMS fee schedule updates, NCCI edit changes, and coding updates.
CMS Fee Schedule
Annual MPFS update • Conversion factor changes
NCCI Edits
Quarterly edit pair updates • New bundling rules
Payer Policies
Filing deadline changes • Prior auth updates
Coding Updates
New CPT codes • Revised descriptions • Deleted codes
Access everything via API
Everything in the Knowledge Network is available programmatically. The free tools are the UI — the API is the product.
# Search payer rules curl https://api.rci.health/v1/knowledge/layers/170001/l4\ ?payer=Medicare \ -H "X-API-Key: YOUR_KEY" # Look up NCCI edits curl https://api.rci.health/v1/knowledge/billing-rules/\ ncci?column1=99213&column2=36415 \ -H "X-API-Key: YOUR_KEY"