- What CHONC Actually Stands For
- Who Issues the Credential
- What the Credential Covers: 14 Competency Areas
- Exam Format and Rules in the Room
- Registration, Fees and Membership Mechanics
- Who Can Sit for It
- Topics That Separate Oncology Coders From Generalists
- Where the Credential Fits in a Career
- Keeping the Credential Active
- Sequencing Your Preparation Around the Competencies
- Frequently Asked Questions
- CHONC stands for Certified Hematology and Oncology Coder, a specialty credential issued by AAPC.
- The exam is 100 multiple-choice questions in four hours; 70 correct answers (70%) passes.
- Active AAPC membership is required, and CPC or COC is not a prerequisite.
- Published competencies span anatomy, compliance rules, ICD-10-CM, E/M, CPT, modifiers and HCPCS Level II.
What CHONC Actually Stands For
CHONC is the abbreviation for Certified Hematology and Oncology Coder. It is a specialty medical coding credential aimed at professionals who translate cancer and blood-disorder care into diagnosis and procedure codes. If you have seen the same letters elsewhere, treat them as unrelated; this article covers only the hematology and oncology coding credential. For quick definitions, see our shorter explainers on what CHONC stands for and the meaning of CHONC.
Hematology and oncology coding is a demanding niche. A single patient visit can involve chemotherapy administration, drug wastage, radiology, laboratory pathology, clinical trial billing and an evaluation and management (E/M) service, all of which must be coded consistently with payer and regulatory rules. The CHONC credential exists to show that a coder can handle that combination.
Who Issues the Credential
The credential is issued by AAPC, historically known as the American Academy of Professional Coders. Exams are delivered through Meazure Learning test centers, or remotely through ProctorU by Meazure Learning live remote proctoring. Because AAPC controls the exam rules, membership requirements and continuing education expectations, the official AAPC materials are the final authority on any policy question. Details such as fees and rules can change, so confirm them against current AAPC sources before you register.
What the Credential Covers: 14 Competency Areas
The 2026 AAPC CHONC Study Guide sample lists top-level competencies, and our preparation framework organizes them into 14 categories. An important caveat: these are published exam-related competencies, not official weighted exam domains. AAPC has not published a numbered, weighted blueprint, so no one can honestly say which area carries the most questions. Our complete guide to the 14 content areas walks through each in detail.
| # | Competency Area | Nature of the Content |
|---|---|---|
| 1 | Medical terminology and anatomy | Foundational vocabulary and body systems |
| 2 | Medical physiology | How blood, organs and disease processes function |
| 3 | Teaching physician guidelines | Compliance and billing rules |
| 4 | Incident-to guidelines | Compliance and billing rules |
| 5 | Split/Shared services | Compliance and billing rules |
| 6 | HIPAA regulations | Privacy and regulatory knowledge |
| 7 | Proper use of the Advance Beneficiary Notice (ABN) | Medicare notice requirements |
| 8 | CMS drug wastage policy | Drug billing rules central to infusion work |
| 9 | Clinical trial services | Research billing and coding |
| 10 | ICD-10-CM coding | Diagnosis coding |
| 11 | E/M code selection using the AMA CPT E/M guidelines | Visit-level coding |
| 12 | CPT coding for common procedures | Procedure coding |
| 13 | CPT and HCPCS Level II modifier usage | Modifier logic |
| 14 | HCPCS Level II coding | Drugs, supplies and services |
Compliance Rules Are Their Own Block
Competencies 3 through 9 form a distinct cluster: teaching physician guidelines, incident-to, split/shared services, HIPAA, the ABN, CMS drug wastage and clinical trials. These are rules-based topics where the right answer depends on who performed or supervised the service and under what conditions. Many coders with general experience have little exposure to some of them, particularly clinical trial services and drug wastage.
CPT Coding for Common Procedures
The published competency retains five subtopics that candidates should expect to work through:
- 30000 Series
- Laboratory and Pathology
- Radiology
- Medicine
- Category III codes
Exam Format and Rules in the Room
The current AAPC guidance supports the following format:
- Questions: 100 multiple-choice questions
- Time: four hours, taken in one sitting
- Passing: 70 correct answers, which equals 70%
- Scoring detail: the split between scored and unscored questions is not disclosed
- Pass rate: a CHONC-specific pass rate is not publicly disclosed
For the scoring math, see the CHONC passing score explained. For what the lack of published pass data means, see what the data shows on CHONC pass rates.
Reference Materials
This is a coding exam, so you work with codebooks. Approved CPT Professional, ICD-10-CM and HCPCS Level II references are allowed under AAPC's current print and electronic rules. The study guide itself is not allowed in the exam. A provided online E/M calculator may be available, and that tool is different from a personal calculator, which is prohibited. Live proctoring and equipment requirements apply, so review them well before test day, especially if you test remotely.
What the Questions Tend to Look Like
AAPC's sample describes assessment as operative or physician-note-based. Expect scenarios built from clinical documentation where you must pick the correct code, modifier or rule application. Hematology/oncology scenarios commonly pair a diagnosis with an infusion, injection or visit, so questions can test several competencies at once: for example, an ICD-10-CM code, an E/M level, a drug HCPCS code and a modifier in the same case. Payer-specific assumptions should matter only when a scenario states them.
Registration, Fees and Membership Mechanics
| Item | Detail |
|---|---|
| Exam fee, one attempt | USD 325 |
| Exam fee, two attempts | USD 399 |
| AAPC membership | Required; observed add-on of USD 229 |
| Non-member exam-only option | No eligibility tier identified |
| Delivery | Meazure Learning test centers or ProctorU by Meazure Learning remote proctoring |
The practical consequence is that your real first-year cost is the exam bundle plus membership, so budget for both. Fees can change; our CHONC certification cost breakdown goes through the pieces, and our exam dates and scheduling guide covers timing.
Who Can Sit for It
You need a valid ID, active AAPC membership and examination authorization. Neither CPC nor COC is a prerequisite, which makes CHONC reachable for coders who have not yet earned a general credential. AAPC recommends specialty experience, though no mandatory degree, references or training-hour total were verified. The study guide sample itself stresses that hands-on specialty coding experience matters and that the guide is not comprehensive. Treat that as a signal: coding oncology cases day to day will teach you things a textbook will not. Our CHONC requirements guide covers the full qualification picture.
Topics That Separate Oncology Coders From Generalists
CMS Drug Wastage Policy
Infusion and injection services often involve single-dose vials where part of the drug is discarded. Candidates must understand how wastage is documented and reported under CMS policy, and how it interacts with HCPCS Level II drug coding and applicable modifiers.
- Know what documentation supports discarded drug amounts
- Connect wastage reporting to HCPCS drug codes and units
- Recognize which modifier concepts apply, and apply them only as the scenario supports
Clinical Trial Services
Cancer patients frequently enroll in trials, which complicates billing because routine care and research-driven services are handled differently. Expect to separate what is billable to the payer from what the study covers.
- Distinguish routine costs from research-only items
- Identify documentation that signals trial participation
- Apply diagnosis and modifier conventions the scenario calls for
Incident-to, Split/Shared and Teaching Physician Rules
Oncology clinics often involve physicians, nurse practitioners, physician assistants and trainees. Who performed which part of a visit determines how it is billed and whether the documentation supports it.
- Incident-to: supervision and established-plan-of-care conditions
- Split/shared: how substantive portions and distinct work are attributed
- Teaching physician: presence and documentation requirements for resident-involved services
ICD-10-CM for Neoplasms and Blood Disorders
Diagnosis coding here means choosing among primary, secondary and metastatic sites, history-of versus active disease, and the proper use of the neoplasm and hematologic code chapters. Follow current official ICD-10-CM guidelines and the sequencing rules they define.
Where the Credential Fits in a Career
CHONC suits coders in oncology practices, hematology practices, infusion centers and related billing operations, as well as coders who want to move into that specialty from general practice coding. Employers value specialty knowledge because oncology billing errors, especially around drugs and trials, are costly. A credential signals that you have been tested on that knowledge. See CHONC jobs for the roles that tend to list it.
On compensation, no verified 2026 CHONC-specific salary premium exists, so avoid any source that quotes one as fact. Our salary analysis and return-on-investment discussion explain how to weigh the credential without invented figures.
Keeping the Credential Active
Certification is not a one-time event. You maintain annual AAPC membership and complete 36 CEUs per two-year cycle for one credential, including eight hematology/oncology CEUs. If you hold multiple AAPC credentials, the totals vary, so check how your combination is counted. No retirement notice for CHONC appeared in the reviewed current issuer sources, and no claim is made about any undisclosed future policy.
Key Takeaway
Plan for membership and CEUs from day one. The eight required hematology/oncology CEUs mean the specialty focus continues after you pass.
Sequencing Your Preparation Around the Competencies
Because no weighted blueprint exists, a balanced plan beats guessing which area is largest. One sensible approach is to build foundations first, then rules, then coding. The sample below is a template; see our CHONC study guide and one-page cheat sheet for more, and CHONC training for course options.
Foundations
- Medical terminology and anatomy
- Medical physiology of blood and cancer processes
Compliance Cluster
- Teaching physician, incident-to and split/shared
- HIPAA and the ABN
Drugs and Research
- CMS drug wastage policy
- Clinical trial services
- HCPCS Level II coding
Code Selection and Full Practice
- ICD-10-CM, E/M, CPT procedures and modifiers
- Timed, full-length practice with your approved codebooks
Rehearse with the same reference books you will bring on exam day so that looking things up is fast. Questions that bundle several competencies reward coders who can move between code sets smoothly. Practice scenarios are available at the main practice test site.
Frequently Asked Questions
CHONC stands for Certified Hematology and Oncology Coder, a specialty medical coding credential issued by AAPC. It is distinct from other credentials that may share similar letters.
The exam has 100 multiple-choice questions to complete in four hours in one sitting. A passing result is 70 correct answers, or 70%. The scored and unscored split is not disclosed.
No. CPC and COC are not prerequisites. You do need a valid ID, active AAPC membership and examination authorization, and specialty experience is recommended.
The specialty exam is USD 325 for one attempt or USD 399 for two attempts, and active AAPC membership is also required, with an observed membership add-on of USD 229. Confirm current pricing with AAPC before registering.
Yes. Approved CPT Professional, ICD-10-CM and HCPCS Level II references are allowed under AAPC's current print and electronic rules. The study guide is not allowed, and a personal calculator is prohibited, though a provided online E/M calculator differs from that rule.