Billing Rules Network

Open catalog of billing forms, type-of-bill codes, place-of-service codes, modifiers, and NCCI edits — searchable and cross-referenced

The open reference for healthcare billing rules. Browse, search, cross-reference. Free.

The Billing Rules Network is RCI’s open catalog of billing requirements. Like Stedi’s EDI Network is for trading partner specifications, the Billing Rules Network is for billing logic — every code, every form, every modifier, cross-referenced.

Browse it at rcintell.com/tools

What’s in the Billing Rules Network

Type of Bill (TOB) Codes

Every institutional claim requires a 4-digit Type of Bill code. The first digit is always 0.

2nd Digit (Facility)	3rd Digit (Classification)	4th Digit (Frequency)
1 = Hospital	1 = Inpatient (Part A)	1 = Admit through discharge
2 = SNF	2 = Inpatient (Part B)	2 = Interim - first claim
3 = Home Health	3 = Outpatient	3 = Interim - continuing
4 = Religious Nonmedical	4 = Other (Part B)	4 = Interim - last claim
5 = (Reserved)	5 = Intermediate care (Level I)	5 = Late charge only
6 = Intermediate care	6 = Intermediate care (Level II)	7 = Replacement
7 = Clinic	7 = Subacute inpatient (Revenue code 019x)	8 = Void/cancel
8 = Special facility	8 = Swing bed	9 = Final claim for HH PPS
9 = (Reserved)	9 = (Reserved)	0 = Non-payment/zero

Common combinations:

TOB	Meaning	When to use
0111	Hospital Inpatient (admit through discharge)	Standard inpatient stay
0121	SNF Inpatient (admit through discharge)	Standard SNF stay
0131	Hospital Outpatient	Outpatient services at hospital
0321	Home Health (Part A)	HH services under Part A
0341	Home Health (Part B)	HH services under Part B
0711	Clinic - Rural Health Clinic	RHC services
0831	Special facility - Ambulatory Surgical Center	ASC services

Place of Service (POS) Codes

Every professional claim requires a POS code.

Code	Name	Modifier Impact	Site-of-Service Differential
11	Office	Standard rates	Non-facility rate
19	Off-campus outpatient hospital	27 modifier	Facility rate
21	Inpatient hospital	-	Facility rate
22	On-campus outpatient hospital	-	Facility rate
23	Emergency room	-	Facility rate
24	Ambulatory surgical center	-	ASC rate
25	Birthing center	-	Non-facility rate
31	Skilled nursing facility	-	Facility rate
32	Nursing facility	-	Facility rate
81	Independent laboratory	-	Non-facility rate

Modifier Reference

Modifiers affect payment, processing, and compliance.

Modifier	Name	When to use	Payment impact
25	Significant, separately identifiable E/M	E/M same day as procedure	Allows separate E/M payment
26	Professional component	Interpreting only (no equipment)	Prof fee only
TC	Technical component	Equipment/staff only (no interpretation)	Tech fee only
59	Distinct procedural service	Unbundling when appropriate	Allows separate payment
XE	Separate encounter	More specific than 59	Allows separate payment
XS	Separate structure	More specific than 59	Allows separate payment
XP	Separate practitioner	More specific than 59	Allows separate payment
XU	Unusual non-overlapping service	More specific than 59	Allows separate payment
76	Repeat procedure by same physician	Same day repeat	Allows separate payment
77	Repeat procedure by another physician	Different physician repeat	Allows separate payment
22	Increased procedural services	Extra work documentation	May increase payment
52	Reduced services	Procedure not completed	Reduces payment

NCCI Edits

National Correct Coding Initiative edits determine which procedures can be billed together.

Column 1	Column 2	Modifier Indicator	Meaning
99213	36415	1	Can unbundle with modifier
99213	81002	0	Cannot unbundle
43239	43235	0	Column 2 included in Column 1
29881	29880	0	Column 2 included in Column 1

Modifier indicators:

• 0 = never allowed to unbundle
• 1 = modifier allowed if criteria met (typically mod 59 or XE/XS/XP/XU)
• 9 = not applicable

Billing Form Reference

Form	Use	Who files	Key fields
CMS-1500	Professional claims	Physicians, NPPs, DME	POS, modifier, diagnosis
UB-04	Institutional claims	Hospitals, SNFs, HH	TOB, revenue code, value codes
ADA	Dental claims	Dentists	Tooth number, surface, area

Revenue Code Reference

Revenue codes on UB-04 identify the type of service.

Code	Description	Common use
0100-0109	Room & board (all-inclusive)	All-inclusive room charges
0110-0119	Room & board (semi-private)	Semi-private room
0120-0129	Room & board (private)	Private room
0250-0259	Pharmacy	Drug charges
0260-0269	IV therapy	IV drug administration
0300-0309	Laboratory	Lab tests
0320-0329	Radiology - diagnostic	X-rays, CTs
0450-0459	Emergency room	ER services
0510-0519	Clinic	Outpatient clinic visits
0636	Pharmacy - drugs requiring detailed coding	Self-administered drugs
0761	Treatment/observation room	Observation stays

Searchable and cross-referenced

Every code links to related codes, required companion codes, exclusions, and real-world usage patterns:

• TOB links to valid revenue codes and facility types
• POS links to modifier requirements and payment differentials
• Modifiers link to NCCI edits that accept them
• Revenue codes link to valid TOB ranges

API access

# Look up a TOB code
curl https://api-dev.rcintell.com/v1/knowledge/billing-rules/tob/0131 \
  -H "X-API-Key: kp_test_..."

# Look up a POS code
curl https://api-dev.rcintell.com/v1/knowledge/billing-rules/pos/22 \
  -H "X-API-Key: kp_test_..."

# Check NCCI edits for a CPT pair
curl https://api-dev.rcintell.com/v1/knowledge/billing-rules/ncci?column1=99213&column2=36415 \
  -H "X-API-Key: kp_test_..."

# Search modifiers
curl https://api-dev.rcintell.com/v1/knowledge/billing-rules/modifiers?q=separate \
  -H "X-API-Key: kp_test_..."

Free to browse

The Billing Rules Network is free and publicly accessible at rcintell.com/tools. No account required to browse. API access requires a free API key.