Medical Coding Interview Questions Freshers Should Prepare for in 2026
Medical Coding Interview Questions Freshers Should Prepare for in 2026 You’ve completed your medical coding course, updated your resume, and finally received the interview call. Then the interviewer asks: “What is medical coding?” Suddenly, all those codes you studied don’t seem quite as easy as they did in class. Don’t worry. Medical coding interviews for freshers are usually less about memorizing hundreds of codes and more about checking whether you understand medical terminology, anatomy, coding guidelines, ICD-10-CM, CPT, HCPCS, and basic coding concepts. If you’re preparing for your first medical coding job in 2026, knowing the questions interviewers commonly ask can help you walk into the interview with much more confidence. Below are 25 important medical coding interview questions and answers for freshers. 1. What is Medical Coding? Answer:Medical coding is the process of converting information from healthcare documentation into standardized medical codes. These codes represent diagnoses, procedures, services, and other healthcare information. Common coding systems include ICD-10-CM, CPT, and HCPCS Level II. 2. What Is the Difference Between Medical Coding and Medical Billing? Answer:Medical coding focuses on reviewing medical documentation and assigning appropriate diagnosis and procedure codes. Medical billing focuses more on using that coded information to prepare and submit claims, follow up on payments, manage denials, and support reimbursement. In simple terms: Coding = Documentation → Codes Billing = Codes → Claims → Reimbursement Both functions work together within the healthcare revenue cycle. 3. What Is ICD-10-CM? Answer:ICD-10-CM stands for International Classification of Diseases, 10th Revision, Clinical Modification. It is used primarily to report diagnoses and health conditions in healthcare settings. A coder uses the documentation and applicable coding guidelines to select the appropriate ICD-10-CM code. 4. What Is CPT? Answer:CPT stands for Current Procedural Terminology. CPT codes are used to report many medical procedures, services, and professional healthcare services. CPT codes are maintained by the American Medical Association (AMA). 5. What Is HCPCS? Answer:HCPCS stands for Healthcare Common Procedure Coding System. HCPCS Level II codes are commonly used to report various products, supplies, services, and items that aren’t represented by CPT codes. For example, certain medical supplies, ambulance services, and durable medical equipment may be reported using HCPCS Level II codes. 6. What Is the Difference Between ICD-10-CM and CPT? Answer: ICD-10-CM primarily represents diagnoses and conditions. CPT primarily represents procedures and professional services. For example, a patient’s diagnosis may be represented using an ICD-10-CM code, while a procedure performed during the encounter may be reported using a CPT code. 7. What Is Medical Necessity? Answer:Medical necessity generally means that a healthcare service or procedure is appropriate and supported by the patient’s condition and clinical circumstances. In coding and billing, documentation and payer requirements help determine whether the reported service is supported. A coder should never assume medical necessity without appropriate documentation and applicable guidelines. 8. What Is a Modifier? Answer:A modifier is used with certain procedure codes to provide additional information about how, where, or under what circumstances a service was performed. Modifiers can provide important details without changing the basic procedure code itself. Examples include Modifier 25 and Modifier 59, although their use depends on specific coding circumstances. 9. What Is Modifier 25? Answer:Modifier 25 is used to indicate that a significant, separately identifiable evaluation and management service was performed by the same physician or other qualified healthcare professional on the same day as another procedure or service, when the documentation supports its use. A common interview follow-up is: “Can Modifier 25 be used simply because two services were performed on the same day?” The answer is no. The documentation must support the requirements for separately reporting the E/M service. 10. What Is Modifier 59? Answer:Modifier 59 is used to indicate that a procedure or service was distinct or independent from another service performed on the same day. It may be appropriate in circumstances involving factors such as a different encounter, procedure, site, organ system, or other qualifying circumstances, depending on the coding rules. It should not be added automatically just to bypass a code-edit issue. 11. What Is a Principal Diagnosis? Answer:For inpatient coding, the principal diagnosis is generally the condition established after study to be chiefly responsible for the admission of the patient to the hospital. The exact determination must follow the applicable official coding guidelines. For outpatient coding, the terminology and sequencing rules are different, so a coder should understand the distinction. 12. What Is a First-Listed Diagnosis? Answer:In many outpatient settings, the first-listed diagnosis is generally the diagnosis, condition, problem, or other reason chiefly responsible for the services provided during the encounter. The correct selection depends on the documentation and the applicable outpatient coding guidelines. 13. What Is Upcoding? Answer:Upcoding occurs when a healthcare service or condition is reported using a code that represents a higher level or greater severity than what is supported by the documentation. For example, reporting a higher-level service without documentation to support that level can be considered upcoding. Accurate coding requires following documentation and coding guidelines rather than trying to increase reimbursement. 14. What Is Downcoding? Answer:Downcoding generally refers to reporting a lower-level code than the service or condition that is appropriately supported by the documentation. Both upcoding and inappropriate downcoding can create problems with coding accuracy and reimbursement. The objective of a professional coder is accurate coding, not maximizing or minimizing payment. 15. What Is a Coding Guideline? Answer:Coding guidelines are rules and instructions that help coders determine how diagnoses and procedures should be reported. They help with areas such as: Code selection Sequencing Combination codes Excludes notes Signs and symptoms Documentation requirements Specific coding situations A good coder doesn’t just memorize codes—they understand how to apply the relevant guidelines. 16. What Is the Difference Between a Symptom and a Diagnosis? Answer:A symptom is something experienced or reported by the patient, such as pain, fever, nausea, or shortness of breath. A diagnosis is a condition identified or documented by the healthcare provider. When a definitive diagnosis has been established, the applicable coding guidelines determine