Medical Billing and Coding Reference Sheets

What’s on these reference sheets

All 10 sheets are free PDFs you can print or keep open while working. Each one downloads directly.

Denial and remittance codes

Why a claim was adjusted, and what the codes on the remittance mean.

• Top 50 Denial Codes Reference Sheet — CO, PR and OA adjustment groups with the meaning and next action for each code, including CO-50 non-covered service and CO-167 benefit not covered
• CARC + RARC Code Reference — claim adjustment reason codes alongside remark codes such as N30, with notes on NCCI bundling edits and member-ID mismatches

Coding and modifiers

Code selection and the modifiers that change how a code is paid.

• Modifier Reference Guide — anesthesia modifiers QX, QK and AD, the GA waiver-of-liability modifier used with an ABN, and the 54/55 split between surgical and post-operative care
• E/M Code Quick Reference — 99202–99215 with medical decision making and total-time thresholds side by side, plus nursing-facility codes such as 99304
• CPT Code Reference by Specialty — code ranges by section, including Pathology and Laboratory 80047–89398, with individual codes such as 90853 group psychotherapy

Claim-form and deadline codes

The codes that go on the claim form, and the deadlines for filing it.

• Place of Service (POS) Code Sheet — a description and billing implication for each setting, including group homes, nursing facilities and comprehensive outpatient rehabilitation facilities
• Revenue Code Reference Sheet — UB-04 institutional revenue codes by range — 0250–0299 pharmacy and supplies, 0360–0369 operating room, 0700–0709 cast room
• Type of Bill (TOB) Code Sheet — type of bill codes by facility, and the fourth frequency digit — X1 for a single bill, X2 and X3 for interim bills, X6 for an adjustment and X7 for a replacement
• Timely Filing Limits by Payer — filing windows by payer, including workers’ compensation ranging from 30 days to 3 years by state, and using a coordination-of-benefits letter on late secondary claims
• Medicare Timely Filing Rules — the one-year limit measured from the date of service, the one-year window for adjustment requests, and the denial codes a late claim receives

These reference sheets are general educational resources. Code sets and payer deadlines change — check them against the code set in force for your date of service and your own payer contracts.