- The One-Page Exam Snapshot
- Fees, Membership and Registration Mechanics
- The 14 Competency Areas at a Glance
- Foundation Knowledge: Terminology, Anatomy and Physiology
- Compliance Rules That Drive Oncology Billing
- Coding Core: ICD-10-CM, E/M, CPT and HCPCS
- Modifier and Drug Billing Quick Hits
- What You Can Bring and How Proctoring Works
- Sequencing Your Review by Domain
- Who Hires CHONC Holders and How to Keep the Credential
- Frequently Asked Questions
- The CHONC exam has 100 multiple-choice questions, a four-hour limit, and a pass mark of 70 correct answers (70%).
- AAPC membership is required to sit the exam; there is no non-member exam-only option.
- The 14 listed areas are published competencies, not officially weighted domains, so study all of them.
- Approved CPT, ICD-10-CM and HCPCS Level II references are allowed; the study guide itself is not.
The One-Page Exam Snapshot
The Certified Hematology and Oncology Coder (CHONC) credential is issued by AAPC and tests whether a coder can translate hematology and oncology documentation into accurate diagnosis, procedure and drug codes. This cheat sheet condenses the facts you most need to carry into exam day. For a broader walkthrough, pair it with the CHONC study guide for first-attempt success.
| Item | What to Remember |
|---|---|
| Issuer | AAPC |
| Format | 100 multiple-choice questions |
| Time | 4 hours, one sitting |
| Passing mark | 70 correct answers, or 70% |
| Scored vs. unscored split | Not disclosed |
| Delivery | Meazure Learning test centers or ProctorU by Meazure Learning remote proctoring |
| Prerequisites | CPC or COC not required; specialty experience recommended |
| Membership | Active AAPC membership required |
| Published pass rate | Not publicly disclosed for CHONC |
The questions are built around operative and physician-note-based assessment. In practice, that means you will read a clinical scenario and decide which code, modifier or billing rule applies. Memorizing code numbers alone will not carry you; you need to apply guidelines to documentation. The breakdown of the CHONC passing score explains the 70-correct threshold in more detail.
Fees, Membership and Registration Mechanics
The specialty exam is priced at USD 325 for one attempt or USD 399 for two attempts. Because an active AAPC membership is required and there is no non-member exam-only tier, factor in the membership cost as well; the observed membership add-on is USD 229. For a full cost walkthrough, see the CHONC certification cost breakdown.
What you need on exam day
- Valid, matching photo identification
- Active AAPC membership
- Examination authorization from AAPC
- For remote testing, equipment that meets the live proctoring requirements
No mandatory degree, reference letters or training-hour total was verified for eligibility. The sample study guide states that CPC or COC is not a prerequisite, though hands-on specialty coding experience is recommended. If you are weighing whether you qualify, the CHONC requirements guide covers eligibility in depth, and the CHONC exam dates and scheduling article covers the logistics of booking.
Key Takeaway
The two-attempt option at USD 399 costs only USD 74 more than a single attempt. If you are uncertain about readiness, that is worth comparing against the cost of a separate retake purchase, but do not let the discount push you into testing before you have worked through every competency area.
The 14 Competency Areas at a Glance
The 14 preparation categories come from the top-level competency bullets in AAPC's 2026 CHONC study guide sample. They are published exam-related competencies, not official weighted domains, and no numbered weighted blueprint was verified. That means you cannot reliably identify a single "largest" domain, so balanced preparation is the safe strategy. The complete guide to all 14 CHONC content areas expands on each one.
| # | Area | Cluster |
|---|---|---|
| 1 | Medical terminology and anatomy | Foundations |
| 2 | Medical physiology | Foundations |
| 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 | Compliance and billing rules |
| 7 | Proper use of the Advance Beneficiary Notice (ABN) | Compliance and billing rules |
| 8 | CMS drug wastage policy | Drug billing |
| 9 | Clinical trial services | Compliance and billing rules |
| 10 | ICD-10-CM coding | Code sets |
| 11 | E/M code selection using the AMA CPT E/M guidelines | Code sets |
| 12 | CPT coding for common procedures | Code sets |
| 13 | CPT and HCPCS Level II modifier usage | Code sets |
| 14 | HCPCS Level II coding | Code sets |
Foundation Knowledge: Terminology, Anatomy and Physiology
Domain 1: Medical terminology and anatomy
Oncology documentation is dense with word parts, and decoding them quickly is what lets you pick the right code.
- Prefixes, roots and suffixes for tumors, blood cells and treatments
- Body systems most involved in cancer care: lymphatic, hematopoietic, respiratory, digestive, reproductive and integumentary
- Site and laterality language used in operative and pathology reports
Domain 2: Medical physiology
Understanding how the body works helps you interpret why a service was performed.
- Blood cell production and common abnormalities
- How cancers spread and how documentation describes primary versus secondary sites
- Why labs, imaging and infusions are ordered for monitoring and treatment
These two areas may feel less "codey," but they underpin everything else. If you cannot tell a primary malignancy from a metastasis in a physician note, ICD-10-CM questions become guesswork.
Compliance Rules That Drive Oncology Billing
Areas 3 through 9 are where oncology practices face real audit exposure, and the exam reflects that. Read each rule for who performs the service, who documents it, and under what conditions it can be billed.
Teaching physician guidelines (Domain 3)
Know when a teaching physician's presence and documentation allow billing for services involving residents.
- What the teaching physician must personally perform or witness
- How documentation must show participation
Incident-to guidelines (Domain 4)
Incident-to rules matter in oncology offices where nonphysician practitioners and clinical staff support ongoing treatment.
- Supervision and initiation-of-care requirements
- Situations where a new problem breaks incident-to eligibility
Split/Shared services (Domain 5)
Understand how a physician and a nonphysician practitioner can share a visit and how the billing practitioner is determined under current rules.
HIPAA regulations (Domain 6)
Expect scenario questions on privacy, permitted disclosures and minimum necessary use of patient information.
Advance Beneficiary Notice (Domain 7)
Know when an ABN is appropriate, what it communicates to the patient, and what it cannot be used for.
Clinical trial services (Domain 9)
Oncology uses clinical trials heavily, so be ready to separate routine care from services tied to the research protocol and to recognize how trial participation affects reporting.
Coding Core: ICD-10-CM, E/M, CPT and HCPCS
ICD-10-CM coding (Domain 10)
Apply the current official ICD-10-CM guidelines. Oncology scenarios typically test whether you can sequence a malignancy correctly, distinguish primary from secondary sites, and recognize when a condition is no longer active. The sample study guide's table of contents lists published diagnostic detail; the sample itself is not the full paid guide, so do not treat it as exhaustive.
E/M code selection (Domain 11)
Selection follows the AMA CPT E/M guidelines. Be comfortable choosing a level by medical decision making or time. A key exam-day detail: the online E/M calculator provided inside the exam environment is different from a prohibited personal calculator, so rely on the provided tool rather than bringing your own.
CPT coding for common procedures (Domain 12)
The published competency keeps five subtopics. Treat each as its own mini-study unit:
- 30000 Series: surgical procedures in that CPT range
- Laboratory and Pathology: tests supporting diagnosis and monitoring
- Radiology: imaging and related services
- Medicine: including services common to oncology care
- Category III codes: temporary codes for emerging services
HCPCS Level II coding (Domain 14)
This area covers the supply, drug and service codes that sit outside CPT. For oncology, think about how drugs are identified and reported alongside administration services.
Key Takeaway
Because operative and physician-note-based assessment is the stated approach, practice extracting the code-driving details from a note: site, laterality, technique, drug name and dose, and who performed each part of the service. Those details decide the answer more often than the code book index does.
Modifier and Drug Billing Quick Hits
Modifier usage (Domain 13)
The exam covers both CPT and HCPCS Level II modifiers.
- Know the purpose of each modifier family: payment-affecting, informational, anatomic and status
- Check whether a scenario describes a distinct service, a reduced service, a repeated service or a service by a different practitioner
- Verify that the modifier is supported by the documentation in the case
CMS drug wastage policy (Domain 8)
Single-dose vial waste is a recurring oncology billing issue. Review the following:
- How discarded drug is documented
- How wastage is reported in line with current CMS guidance
- Why the amount administered and the amount discarded must both be recorded
Apply current official CPT, ICD-10-CM, HCPCS and regulatory guidance throughout. Payer-specific assumptions matter only when a scenario states them, so do not import outside payer rules into your answers.
What You Can Bring and How Proctoring Works
The exam allows approved CPT Professional, ICD-10-CM and HCPCS Level II references under current print and electronic rules. The study guide is not allowed. Because live proctoring applies, confirm your setup well before test day.
- Allowed: approved code books and the provided online E/M calculator
- Not allowed: the study guide and a personal calculator
- Remote testing: follow ProctorU by Meazure Learning equipment and environment requirements
- Test center: Meazure Learning locations
For a candid look at how demanding the test is, read how hard the CHONC exam really is, and note that the CHONC pass rate article explains why no verified figure is available.
Sequencing Your Review by Domain
Because no official weighting exists, a sensible plan covers all 14 areas and front-loads the ones that build on each other. Here is one sequencing approach tied to the CHONC areas:
Foundations
- Medical terminology and anatomy
- Medical physiology
Billing rules
- Teaching physician, incident-to and split/shared services
- HIPAA, ABN, drug wastage and clinical trials
Diagnosis and E/M
- ICD-10-CM coding for malignancy and hematology scenarios
- E/M selection using the AMA CPT guidelines
Procedures, modifiers and HCPCS
- Common-procedure CPT subtopics
- Modifier usage and HCPCS Level II
- Timed full-length practice with your references
Adjust the pace to your background. A coder with strong hematology experience may compress the foundations, while someone from a primary care setting may need extra time on infusion and drug billing. Use the CHONC practice tests to see which areas need more attention, and revisit weak areas before the timed run.
Who Hires CHONC Holders and How to Keep the Credential
Employers that bill for cancer and blood-disorder care are the natural fit: oncology and hematology practices, cancer centers, infusion services and the billing organizations that support them. The credential signals that you understand the specialty's combination of drug billing, clinical trial rules and complex diagnosis coding. Browse CHONC jobs for the kinds of roles that value it.
On pay, no verified 2026 salary premium for CHONC exists, so treat any specific figure you see with caution. The CHONC salary guide and the analysis of whether CHONC is worth it discuss how to weigh the credential's value without relying on invented numbers.
Maintenance at a glance
- Keep your AAPC membership active every year
- Earn 36 CEUs per two-year cycle for one credential
- Include eight hematology/oncology CEUs in that total
- If you hold multiple credentials, totals vary, so check your own requirements
Frequently Asked Questions
The exam has 100 multiple-choice questions with four hours to complete it in a single sitting. The split between scored and unscored questions is not disclosed.
You need 70 correct answers, which equals 70%. A CHONC-specific pass rate has not been publicly disclosed, so avoid relying on unofficial numbers.
No. CPC and COC are not prerequisites. AAPC recommends specialty experience, and an active membership plus exam authorization and valid ID are required.
Approved CPT Professional, ICD-10-CM and HCPCS Level II references are allowed under current print and electronic rules. The study guide is not permitted, and a provided online E/M calculator is distinct from a prohibited personal calculator.
No verified numbered weighted blueprint exists. The 14 areas are published competencies from the study guide sample, so prepare across all of them rather than betting on one heavy area. Read the overview of what CHONC certification is for broader context.