CPT Codes: What They Are, How to Look Them Up, and How to Use Them
A wrong CPT code can sink an otherwise clean claim. The payer reads the code, decides what service you performed, and pays or denies based on that one short string of characters. If you bill, code, or manage a practice, you need to know how CPT codes work, where to look them up, and how they apply to your specialty. This guide covers the basics, a step-by-step CPT code lookup process, and the main occupational therapy CPT codes with the 2026 billing rules that go with them.
What Is a CPT Code?
A CPT code is a five-character code that describes a medical, surgical, or diagnostic service a provider performed. CPT stands for Current Procedural Terminology, and the American Medical Association (AMA) maintains it. Billers put CPT codes on claims so payers know exactly which service to pay for.
Every service has its own code. A 15-minute block of therapeutic activities is 97530. A moderate-complexity office visit for an established patient is 99214. An MRI of the brain without contrast is 70551.
The AMA first published CPT in 1966. Today it is the standard code set used to report physician and other health care services on claims to Medicare, Medicaid, and commercial payers. The AMA owns the copyright, which is why full code descriptions are not free to copy and share online.
CPT Medical Abbreviation: What Does CPT Stand For?
In billing, coding, and insurance, CPT means Current Procedural Terminology. That is the meaning you need on a claim.
The same three letters show up in clinical notes with other meanings. In a chart, CPT can also mean chest physiotherapy or cognitive processing therapy, a treatment for post-traumatic stress. If you see CPT in a progress note rather than on a claim form, check the context before you assume it refers to a code.
Why CPT Codes Matter for Getting Paid
CPT codes do three jobs at once. They tell the payer what you did, they set the payment rate for that service, and they trigger the payer’s rules about bundling, frequency, and documentation.
Picture a small family practice that bills a visit as 99213 when the note supports 99214. The claim pays, but at a lower rate. If that happens a few times a week, the practice leaves real money on the table. The opposite mistake is worse. Billing a higher code than the documentation supports can lead to audits and repayment demands.
CPT codes also work together with diagnosis codes. The CPT code says what you did. The ICD-10-CM code says why. The payer checks that the two make sense together, and a mismatch is a common reason for denial.
The Three Categories of CPT Codes
CPT has three categories. Most of your daily billing uses Category I.
| Category | Format | What it is for | Payment |
|---|---|---|---|
| Category I | Five digits (for example, 99214) | Procedures and services that are widely performed and approved | Paid by payers |
| Category II | Four digits plus the letter F | Tracking quality and performance measures | Usually no payment value |
| Category III | Four digits plus the letter T | Emerging technology and new services, tracked temporarily | Varies by payer, often treated as investigational |
Category II codes are optional supplemental tracking codes. They help report quality measures and do not replace a Category I code on the claim. Category III codes let the AMA collect data on new services before they earn a permanent Category I code. Many payers do not cover them, so check the payer’s policy before you bill one.
How CPT Codes Are Organized
Category I codes are grouped into six sections by type of service.
| Section | Code range | Examples |
|---|---|---|
| Evaluation and Management (E/M) | 99202 to 99499 | Office visits, hospital visits, consultations |
| Anesthesia | 00100 to 01999 | Anesthesia for surgery and procedures |
| Surgery | 10004 to 69990 | Skin procedures, fracture care, cardiac and eye surgery |
| Radiology | 70010 to 79999 | X-rays, CT, MRI, ultrasound, nuclear medicine |
| Pathology and Laboratory | 80047 to 89398 | Blood tests, cultures, pathology exams |
| Medicine | 90281 to 99607 | Vaccines, therapy services, cardiology tests, physical medicine |
Occupational and physical therapy codes sit in the Medicine section, in the 97000 range.
Example: the New Patient CPT Code and Established Patient Codes
Office visit codes are the most billed codes in many practices, so they make a good example. Use 99202 to 99205 for a new patient and 99211 to 99215 for an established patient. For most of these, you choose the level based on either the medical decision making or the total time you spent on the date of the visit. The higher the level, the higher the payment, and the more your note has to support it.
CPT vs. ICD-10 vs. HCPCS
New billers often mix up the three main code sets. They answer different questions.
| Code set | Question it answers | Maintained by | Example |
|---|---|---|---|
| CPT (HCPCS Level I) | What service was performed? | AMA | 97530 |
| ICD-10-CM | Why was it performed (diagnosis)? | CDC and CMS | M25.511 |
| HCPCS Level II | Which supplies, drugs, or equipment were used? | CMS | J1100 |
The HCPCS vs CPT question comes up because CPT is technically Level I of HCPCS. Level II is the part CMS runs. It uses a letter followed by four digits and covers things CPT does not, such as durable medical equipment, many injectable drugs, and ambulance services. A single claim often carries all three code types.
CPT Code Lookup: How to Find the Right Code
A CPT code lookup is simple when you know the service. It gets harder when the note is vague or the code descriptions overlap. These tools cover most needs.
Where to search
- AMA CPT code lookup. The AMA offers a search on its website. Access has been free with registration, with daily search limits, so check the current terms before you rely on it.
- CMS Physician Fee Schedule Look-Up Tool. This free tool lets you search a code and see Medicare payment amounts, global periods, and status indicators. It is the quickest way to learn what Medicare pays for a code.
- Payer portals. Large payers publish their own code lists and policies. These tell you whether a code is covered, not just what it means.
- Paid coding tools. Encoder software, AAPC Codify, and the current-year CPT Professional book show full descriptions, guidelines, and coding tips. Most billing teams use one of these.
Steps to choose the correct code
- Start with the note. Read what the provider actually documented. Code from the documentation, not from memory or habit.
- Search in plain words. Type the service (“therapeutic activities,” “knee MRI,” “new patient visit”) into your tool. A keyword search is usually faster than browsing by section.
- Read the full description and the section guidelines. Short descriptions leave out rules, such as time requirements or what is included in the code.
- Confirm the year. Use the code set that matches the date of service. A code deleted in January will deny.
- Check modifiers and bundling. Look up the CMS National Correct Coding Initiative (NCCI) edits to see if two codes can be billed together, and whether a modifier is needed.
- Check the payer. A valid CPT code is not always a covered one. Verify coverage and prior authorization rules for that payer.
A lookup tells you what a code means. It does not tell you if the payer will pay for it. Free sites also tend to show shortened or outdated descriptions, so confirm anything important against the current-year source.
Occupational Therapy CPT Codes
Occupational therapy (OT) billing relies on a small group of codes that repeat across nearly every visit. Most are timed codes billed in 15-minute units. A few are untimed and billed once per visit. Many of these codes also appear in physical therapy billing, so you may see them in PT guides too.
Evaluation and re-evaluation codes (97165 to 97168)
Evaluations are untimed. You bill one per evaluation, and the code depends on the complexity of the case.
| Code | Description | Typical time |
|---|---|---|
| 97165 | OT evaluation, low complexity | 30 minutes |
| 97166 | OT evaluation, moderate complexity | 45 minutes |
| 97167 | OT evaluation, high complexity | 60 minutes |
| 97168 | OT re-evaluation | 30 minutes |
Complexity comes from three things: the patient’s occupational profile and history, the number of performance deficits found, and the clinical decision making needed. A low-complexity evaluation involves a brief history and one to three deficits. A high-complexity evaluation involves an extensive history and five or more deficits. The typical times are guides. They are not billing requirements.
Common OT treatment codes
| Code | Description | Billed as |
|---|---|---|
| 97530 | Therapeutic activities (dynamic activities to improve function) | Each 15 minutes |
| 97110 | Therapeutic exercise (strength, range of motion, flexibility) | Each 15 minutes |
| 97112 | Neuromuscular re-education (balance, coordination, posture) | Each 15 minutes |
| 97140 | Manual therapy techniques | Each 15 minutes |
| 97535 | Self-care and home management training (ADLs, adaptive equipment) | Each 15 minutes |
| 97129 and 97130 | Therapeutic interventions for cognitive function | First 15 minutes, then each additional 15 |
| 97150 | Group therapeutic procedures (two or more patients) | Untimed, per patient |
| 97760 and 97763 | Orthotic management and training | Each 15 minutes |
The therapeutic activity CPT code (97530) is one of the most-billed OT codes, because it covers the functional, task-based work that sets OT apart. The therapeutic exercise CPT code (97110) is also frequently billed. Because these two can look similar in a note, payers often review them closely. The documentation should show what the therapist did, why it was needed, and how it ties to the patient’s goals. Where static splints are made, separate codes in the 29000 range, such as 29125 and 29130, may apply.
Timed codes and the 8-minute rule
Medicare counts minutes for timed codes. Under the CMS 8-minute rule, you add up all the minutes of timed treatment in the visit, then convert the total to units.
| Total timed minutes | Units to bill |
|---|---|
| 8 to 22 | 1 |
| 23 to 37 | 2 |
| 38 to 52 | 3 |
| 53 to 67 | 4 |
| 68 to 82 | 5 |
Here is a fictional example. An OT does 10 minutes of therapeutic activities (97530) and 10 minutes of therapeutic exercise (97110) with a Medicare patient. The total is 20 minutes, so Medicare allows 1 unit, billed under the code with more minutes. A payer that follows the AMA’s midpoint approach, where each code is judged on its own, might allow 1 unit of each. Payers differ, so confirm the rule in each contract.
Modifiers and Medicare rules for OT
CPT codes and modifiers work as a pair. For OT, the main modifiers to know are:
- GO.
Shows the service was delivered under an occupational therapy plan of care. Medicare requires it on OT therapy codes. - CO.
Shows the service was furnished in whole or in part by an occupational therapy assistant. Medicare pays these services at 85 percent of the fee schedule rate. - KX.
Confirms the services above the annual threshold are medically necessary. For 2026, CMS set the KX threshold at $2,480 for OT. It applies separately from the combined PT and speech-language pathology threshold. Claims over the amount without KX are denied.
Medicare also expects a certified plan of care, regular progress reports, and clear records of treatment minutes. Document the total timed minutes and the total treatment time, along with the start and stop times where your payer asks for them. Other payers add their own rules, so keep a short payer-by-payer reference.
Common CPT Coding Mistakes That Lead to Denials
Most CPT-related denials come from a short list of avoidable errors.
- Using an outdated code. A deleted or revised code rejects at once. Update your charge master every January.
- Wrong units on timed codes. Counting each code’s minutes separately for a Medicare patient inflates units and invites audits.
- Missing modifiers. Leaving off GO, CO, 25, or 59 when needed is a frequent cause of denials and underpayments.
- Unbundling. Billing separately for services the payer considers part of another code breaks NCCI edits.
- Code and note do not match. If the documentation does not support the level or service billed, the claim fails on review.
- Diagnosis does not support the service. A valid CPT code with a diagnosis that does not justify it is often denied for medical necessity.
Keep Up With Yearly CPT Changes
The AMA updates CPT every year, and changes take effect on January 1. For 2026, the AMA reported 418 changes: 288 new codes, 84 deletions, and 46 revisions. The update included new telemedicine E/M code ranges, which replaced older telephone-only codes. The AMA usually publishes the next year’s code set in the fall, so now is a good time to review your top codes.
A simple habit helps. Each fall, pull your 20 most-billed CPT codes and compare them to the new descriptions. Update your charge master and train your staff on any change before January claims go out.
If CPT coding errors are driving denials in your practice, our team can review your last 90 days of claims and show you where the codes and the documentation do not line up.
