- The CMC exam has four sections: Terminology, ICD-10-CM Coding, CPT Coding, and Coding Scenarios.
- Terminology is closed-book; Sections II-IV allow coding manuals and a medical dictionary.
- The exam is 133 questions, six hours, written-answer (fill-in-the-blank, matching, and scenarios) - not multiple choice.
- Passing requires a 70% aggregate score across all four sections combined.
Overview: How the CMC Exam Is Built
The Certified Medical Coder (CMC) credential, awarded by the Practice Management Institute (PMI), is built around outpatient medical coding. Unlike many multiple-choice certification exams, the CMC exam is a written-answer test with fill-in-the-blank responses, matching, and coding scenarios that mirror actual outpatient coding work. Every question on the exam falls into one of four domains, and understanding how those domains are structured - and which parts of the exam are open-book versus closed-book - is the single most important thing you can do before exam day.
This guide breaks down all four content areas exactly as PMI's currently linked public sample handbook (dated January 10, 2018) names them, along with what candidates need to master in each one. If you haven't yet reviewed the overall exam structure, our CMC Study Guide covers the bigger picture of preparing for exam day, and How Hard Is the CMC Exam? digs into why the written-answer format catches many candidates off guard.
Domain 1: Terminology
What This Domain Covers
Terminology tests your command of medical vocabulary, anatomy references, abbreviations, and word-building rules (prefixes, suffixes, and root words) without any reference materials. This is the one section of the exam where you cannot look anything up.
- Anatomical and physiological terms tied to outpatient encounters
- Prefixes, suffixes, and combining forms used to decode unfamiliar medical terms
- Standard clinical abbreviations found in physician documentation
- Disease processes and procedural language that show up across specialties
Because Terminology is closed-book while the other three sections permit reference materials, this domain rewards memorization rather than lookup speed. Candidates who treat Terminology as an afterthought - assuming they can "figure it out" from context during the exam - consistently lose more points here than in any other domain, simply because there is no manual to fall back on.
Key Takeaway
Drill Terminology flashcards and word-part breakdowns early in your prep, since it's the only closed-book section and the easiest place to lose avoidable points.
Domain 2: ICD-10-CM Coding
What This Domain Covers
This section tests your ability to assign accurate diagnosis codes from ICD-10-CM based on documentation excerpts. You'll need your current-year ICD-10-CM manual on hand, since this section allows coding manuals and a medical dictionary.
- Selecting the correct code category, laterality, and level of specificity
- Applying ICD-10-CM guidelines for sequencing and combination codes
- Recognizing when documentation is insufficient to code to the highest specificity
- Navigating the alphabetic index and tabular list efficiently under time pressure
Speed matters here as much as accuracy. With 133 questions spread across a six-hour exam covering four domains, you can't afford to spend excessive time flipping through your ICD-10-CM manual on every question. Practicing with your actual current-year manual - tabbing frequently used sections, learning the index layout - pays off far more than passive review. For a breakdown of exactly what "passing" means across domains, see our guide to the CMC Passing Score.
Domain 3: CPT Coding
What This Domain Covers
CPT Coding tests your ability to assign correct procedure and service codes from the Current Procedural Terminology manual, again using your current-year manual as an open-book reference.
- Evaluation and Management (E/M) code selection for outpatient encounters
- Surgical, radiology, and laboratory code sets relevant to outpatient settings
- Modifier usage and bundling rules
- HCPCS Level II codes for supplies, durable medical equipment, and services not captured by CPT
Since PMI requires current-year ICD-10-CM, CPT, and HCPCS manuals for the exam (the medical dictionary can be from any year), this is also where outdated study materials can quietly sabotage a candidate. Codes get added, revised, and deleted every year - practicing with a manual that's even one cycle behind can teach you the wrong answer with total confidence. Always confirm your codebooks are current on your actual exam date and follow the handbook provided for your specific appointment.
Domain 4: Coding Scenarios
What This Domain Covers
Coding Scenarios is the domain that pulls everything together. Instead of isolated code lookups, you're given realistic outpatient documentation excerpts and asked to work through the full coding process - diagnosis, procedure, and modifier assignment together, exactly as you would in an actual coding role.
- Reading a chart note or encounter summary and extracting codable information
- Assigning ICD-10-CM and CPT codes together in a single coherent case
- Applying modifiers and sequencing rules in context rather than in isolation
- Justifying code selection based on documentation specificity
This is also the domain most candidates underestimate during self-study, because most generic practice materials present multiple-choice questions instead of real coding exercises. The CMC exam itself never uses multiple choice - it's fill-in-the-blank, matching, and worked scenarios - so practicing exclusively with multiple-choice drills builds the wrong muscle. Effective preparation uses original written coding exercises and full worked cases, not replica-style multiple-choice quizzes. Our CMC Cheat Sheet is designed around this scenario-based format rather than multiple-choice recall.
Key Takeaway
Practice full worked cases, not isolated code lookups - Coding Scenarios rewards candidates who can move fluidly between ICD-10-CM, CPT, and modifier logic within a single patient encounter.
Format, Timing, and Grading
Understanding the domains only helps if you also understand how the exam is administered. PMI's currently linked public sample handbook (dated January 10, 2018) specifies the section names used above, and the current official program page specifies 133 questions across a six-hour examination window. This is a substantial amount of time, but it's spread across four domains of varying depth, so pacing matters.
| Domain | Reference Materials Allowed | Core Skill Tested |
|---|---|---|
| Terminology | Closed-book | Vocabulary, word parts, abbreviations |
| ICD-10-CM Coding | Coding manuals + medical dictionary | Diagnosis code assignment |
| CPT Coding | Coding manuals + medical dictionary | Procedure/service code assignment |
| Coding Scenarios | Coding manuals + medical dictionary | Full-encounter coding application |
The exam is hand-graded and verified twice, and passing requires an aggregate score of at least 70% across the full exam - not a minimum score in each individual domain. That aggregate structure is worth understanding fully before you decide where to focus your remaining study hours; our CMC Pass Rate article walks through what that scoring approach means in practice.
Scheduling Your Domains by Week
Because the four domains differ so much in format - closed-book Terminology versus open-book code assignment versus integrated scenarios - it helps to sequence your study time deliberately rather than reviewing everything at once. A simple four-week structure built around the domains themselves works better than generic weekly templates, since each week targets a distinct skill.
Terminology Foundations
- Build word-part flashcards (prefixes, suffixes, roots)
- Memorize high-frequency abbreviations from outpatient documentation
- Test yourself closed-book, since this is the only section without references
ICD-10-CM Coding
- Practice navigating your current-year ICD-10-CM manual by index and tabular list
- Work diagnosis-coding exercises from real documentation excerpts
- Time yourself to build lookup speed for the timed exam
CPT and HCPCS Coding
- Review E/M leveling and modifier rules using your current-year CPT manual
- Practice HCPCS Level II code assignment for supplies and DME
- Cross-reference codes across manuals to catch bundling issues
Coding Scenarios and Full Review
- Work full outpatient case studies combining diagnosis, procedure, and modifiers
- Simulate six-hour pacing with all four codebooks at hand
- Review weak domains identified in earlier weeks
This sequencing isn't a substitute for full exam readiness - it's a way to make sure each domain gets dedicated, focused attention instead of being buried in generic review. If you want a deeper walkthrough of exam-day logistics and rescheduling rules, our CMC Exam Dates guide covers scheduling windows and the 14-day notice requirement in detail.
Key Takeaway
Sequence your study by domain difficulty and reference-material access: closed-book Terminology first, then build up to the integrated Coding Scenarios section last.
Frequently Asked Questions
PMI's public sample handbook names the four sections - Terminology, ICD-10-CM Coding, CPT Coding, and Coding Scenarios - but grading is based on an aggregate score of at least 70% across the full exam rather than published individual weights for each section.
No. The Terminology section is closed-book, while Sections II through IV (ICD-10-CM Coding, CPT Coding, and Coding Scenarios) permit coding manuals and a medical dictionary.
You need current-year ICD-10-CM, CPT, and HCPCS manuals current on your actual exam date. The medical dictionary can be from any year. Always follow the handbook supplied for your specific appointment.
No. It's a written-answer exam using fill-in-the-blank responses, matching, and coding scenarios - not multiple choice. Practice materials that only offer multiple-choice drills don't reflect the actual test format.
Retakes require at least a 60-day waiting period along with an additional fee. Use that time to focus study efforts on whichever domains felt weakest, particularly Coding Scenarios if your issue was applying codes together rather than looking them up individually.
Mastering all four CMC domains takes deliberate, format-specific practice rather than generic exam cramming. Explore more first-hand practice questions and worked coding scenarios on CMC Exam Prep, and if you're still weighing whether this credential fits your career path, our Is the CMC Certification Worth It? analysis and CMC Jobs overview are good next stops.