How to become a radiation therapist

1. 1Take math and science in high school

   Time: 4 years (high school)Sources 3

   Radiation therapy programs expect a solid base in algebra, biology, chemistry and ideally physics, because the coursework covers how radiation interacts with tissue and how doses are measured. Many programs are selective and rank applicants by grades in these subjects. Volunteering or shadowing in a hospital cancer center is useful: it shows you what daily treatment looks like and gives you something concrete to discuss in a program interview.

2. 2Complete prerequisites and apply to an accredited program

   Time: 6 months-1 yearCost: VariesSources 3, 4, 10

   Most associate and bachelor's programs ask for college-level anatomy and physiology, algebra, physics or chemistry, and English before admission. Seats are limited because each student needs clinical placements, so compare several programs. Use the JRCERT program finder to confirm the program is accredited in radiation therapy; graduating from an ARRT-approved program is what makes you eligible for the national exam.

3. 3Finish the radiation therapy program, including clinical rotations

   Time: 2-4 years (about 1 year for certificate programs)Cost: $4,650-$10,470 per year (median public in-state tuition)Sources 1, 3, 4

   Coursework covers radiation physics, radiobiology, oncology, treatment planning, patient care and radiation protection. Clinical rotations put you in working cancer centers, where you position patients and run treatments under supervision. ARRT requires an associate degree or higher before you sit for the exam; the degree can be in any field. Experienced X-ray techs can take a shorter certificate program instead.

4. 4Pass the ARRT radiation therapy exam

   Time: 1-3 months after graduationCost: $225 application feeSources 2, 4

   Apply through ARRT's primary pathway once your program confirms you have completed it, and meet ARRT's ethics requirement, which includes disclosing certain criminal or disciplinary history. You then schedule the computer-based exam at a testing center. After you pass, you can use the R.T.(T)(ARRT) credential. The exam covers radiation protection, treatment planning, treatment delivery and patient care.

5. 5Get your state license and start working

   Time: 2-8 weeksCost: State fee (varies)Sources 3, 5

   Most states license or certify radiation therapists, and many accept ARRT certification as the basis for it. Check your state's rules in the CareerOneStop License Finder and with the state radiation control or health agency. Employers usually also require current CPR or basic life support certification. New therapists often start on a team rotation across several treatment machines and the CT simulator.

Programs, tuition and graduates’ earnings

U.S. Department of Education, College Scorecard (most recent cohorts, released 2026-10-15). Scorecard groups programs by 4-digit field, so a row can include related programs. Tuition is the median published undergraduate tuition and fees of the colleges offering the program (shown only for undergraduate credentials); debt is the median of programs’ median federal loan debt at completion; earnings are the national median for the field and credential four years after completion.

Requirements differ by state. Check your state’s rules in the CareerOneStop License Finder (U.S. Department of Labor) before you enroll.

Precision

A patient set up a few millimeters off can send radiation into healthy tissue, so every alignment and setting has to be exact.

Compassion

Therapists see frightened, often exhausted cancer patients almost every weekday for weeks and set the tone for each visit.

Physics and math sense

Understanding beam energy, dose and geometry helps you spot when a plan or a setup does not look right.

Comfort with complex equipment

Linear accelerators, imaging systems and treatment software each need careful operation and quick troubleshooting.

Clear communication

You explain each step to patients and relay side effects accurately to nurses, dosimetrists and the oncologist.

O*NET 31.0 rates these skills as most important for the occupation: reading comprehension, active listening, critical thinking, speaking, monitoring.

Training cost

$9.5K–$42.1K

Before financial aid

Time

2-4 years

Typical path

Median pay

$105,310

All US jobs: $50,980

Payback once qualified

Under 1 year

Pay above the all-jobs median vs. cost

Low: 2 years x College Scorecard median in-state public tuition for allied health associate programs ($4,650/yr) + ARRT primary application fee $225. High: 4 years x the bachelor's median ($10,470/yr) + $225. Excludes books, uniforms, travel to clinical sites, state license fees and living costs; private and out-of-state programs cost more.

Rough guide only: ignores taxes, aid, interest and earnings given up during training. How we calculate it.

• Medical dosimetrist

  Complete a JRCERT-accredited dosimetry program of at least 12 months, hold a bachelor's degree and pass the MDCB exam to plan doses rather than deliver them.

• Radiologic technologist$80,110 median

  Therapists sometimes add a radiography credential through a separate accredited program to work in diagnostic imaging.

• MRI technologist$95,480 median

  Some therapists add MRI by completing supervised clinical MRI training and passing ARRT's separate MRI certification exam.

• Physician assistant$135,880 median

  Requires a bachelor's degree, prerequisite courses and a master's-level PA program, followed by the national PA exam.