Radiation therapists
Also called Radiotherapist, RTT, Therapeutic radiologic technologist, Radiation therapy technologist, Linear accelerator technologist
In brief
In May 2025, BLS counted 17,070 US radiation therapists, with median pay of $105,310 a year. Of the BLS counts since 2003, the highest was 18,700, in May 2024. The earliest figure here is an estimate of 3,000 from 1964, not measured the same way as today's count. The last full technology era for radiation therapists: Image-guided radiation therapy, 2000 to 2018. IGRT extended the average treatment appointment time per fraction due to imaging and couch correction steps, which modestly increased staffing requirements per treatment vault.
What the sources say
Official outlook
BLS projects employment to grow 2.8% from 2025 to 2035.
AI exposure studies
- 17.1% of this job's tasks are exposed to large language models. Not a forecast of job losses. Eloundou and others, 2023
Data as of BLS OEWS May 2025; BLS Employment Projections 2025-35. BLS publishes these counts as yearly survey snapshots and cautions against reading them as a precise trend. In May 2021 BLS changed how it estimates these counts (a model-based method using three years of survey data) and moved fully to the 2018 occupation codes, so part of a change across 2021 can come from the method rather than the work.
Last updated .
Cite this page
Future History. (2026, October 11). Radiation therapists: jobs and pay since 1964 [Data set; data as of BLS OEWS May 2025; BLS Employment Projections 2025-35]. https://futurehistory.earth/timeline/29-1124
Future History. "Radiation therapists: jobs and pay since 1964." Data as of BLS OEWS May 2025; BLS Employment Projections 2025-35. Last modified October 11, 2026. https://futurehistory.earth/timeline/29-1124.
@misc{futurehistory_29_1124, author = {{Future History}}, title = {Radiation therapists: jobs and pay since 1964}, year = {2026}, month = oct, howpublished = {\url{https://futurehistory.earth/timeline/29-1124}}, note = {Last updated 2026-10-11. Data as of BLS OEWS May 2025; BLS Employment Projections 2025-35}, }
The access date is today's date on your device.
≈ $102,610 in 2024 prices (derived by us, CPI-adjusted)
January 29, 1896: Emile Grubbe, a 21-year-old medical student in Chicago, irradiates a patient's recurrent breast cancer tumor approximately six weeks after Roentgen's announcement of X-rays. Most historians of radiation oncology regard this as the earliest documented therapeutic use of X-rays in the United States, though the treatment predates any concept of dose measurement or radiation protection.
Eddy C. Jerman convenes 13 X-ray operators in Chicago to form the American Association of Radiological Technicians, the forerunner of ASRT. The founding group recognizes that untrained operators and absent radiation protection standards are creating a humanitarian disaster among X-ray workers. The organization would rename itself the American Society of X-Ray Technicians in 1932 and the American Society of Radiologic Technologists in 1964, marking the formal inclusion of radiation therapy workers as a distinct recognized specialty.
October 27, 1951: The first patient to receive cobalt-60 teletherapy treatment in North America is treated at the War Memorial Children's Hospital in London, Ontario. Within a few years, cobalt machines spread rapidly through US academic and community cancer centers, creating for the first time a distinct class of hospital worker whose primary job was to operate a specialized radiation therapy device. The cobalt era directly drove the 1964 ARRT credentialing milestone.
The American Registry of Radiologic Technologists administers its first separate certifying examination for radiation therapy technology, formally recognizing the specialty as distinct from diagnostic radiography. This is the practical founding date of the modern radiation therapist occupation. Before 1964, radiation therapy workers sat the same ARRT examination as diagnostic X-ray technicians. The 1964 separate exam acknowledged that treating cancer with radiation required a different and specialized body of clinical knowledge.
The Joint Review Committee on Education in Radiologic Technology (JRCERT) is established in 1969 (incorporated 1971) to accredit educational programs in radiologic sciences, including radiation therapy. The 1968 "Essentials of an Acceptable School of Radiation Therapy Technology," jointly adopted by the ACR, ASRT, and AMA, provided the foundational accreditation standard. JRCERT remains the only US Department of Education and CHEA-recognized accreditor for radiation therapy educational programs today.
April 1994: The first patient receives intensity-modulated radiation therapy (IMRT) using the MIMiC device, beginning a technology era that would transform both the clinical scope and the technical demands of the radiation therapist role. IMRT enabled curative treatment of prostate, head-and-neck, and gynecologic cancers with dramatically reduced normal-tissue toxicity compared to 3D conformal radiotherapy, expanding the population eligible for radiation therapy and reshaping the case mix radiation therapists encounter daily.
ARRT formalizes the associate degree requirement: since 2015 all candidates for the ARRT Radiation Therapy (T) credential must hold at least an associate degree from a JRCERT-accredited program. This raised the profession's entry floor and signaled a broader trend toward bachelor's-degree entry, which several major cancer centers now prefer or require in job postings. The educational baseline is one reason median wages for radiation therapists have consistently ranked among the highest of the allied health technologist occupations.
The Elekta Unity MR-Linac enters clinical use, inaugurating the adaptive therapy era for radiation therapists. The Unity integrates a 1.5T MRI with a radiotherapy linac, allowing real-time diagnostic-quality soft-tissue imaging at the treatment position. Online adaptive replanning, previously a research capability, becomes a clinical workflow: the therapist manages patient positioning inside a combined MR-linac system, oversees AI-generated contour review, and coordinates a 45-90 minute session that is radically different from the 15-minute standard linac fraction. The adaptive therapy era represents the most significant expansion of therapist cognitive scope since the introduction of IGRT.
Will AI replace radiation therapists? What the research says
Each figure is stated by the named source; we publish no forecasts of our own. Where sources disagree, we show the disagreement rather than an average.
Each figure is stated by the named source; we publish no forecasts of our own. Where sources disagree, the spread is the honest signal.
What's changing day to day for radiation therapists
Three parts of your work where AI is already doing real lifting, and what stays yours.
AI is sitting alongside you hereReview and approve AI-generated organ-at-risk and target contours on daily adaptive therapy sessions, at adaptive therapy linac sites (Varian Ethos, Elekta ONE Online, Unity MR-Linac), reviewing the AI auto-segmented contours produced on the daily CBCT or MR image
Review and approve AI-generated organ-at-risk and target contours on daily adaptive therapy sessions, at adaptive therapy linac sites (Varian Ethos, Elekta ONE Online, Unity MR-Linac), reviewing the AI auto-segmented contours produced on the daily CBCT or MR image; identifying and correcting contour errors (over-contouring bowel into bladder, missed OAR segment, shifted target due to anatomical change); confirming the contour set is clinically acceptable before the adaptive plan optimizer generates a new fraction plan.[7],[8]
This is the fastest-growing new responsibility in the radiation therapist's scope. Develop your anatomy knowledge beyond what was traditionally required: understand which OAR boundaries the AI consistently under- or over-contours for each treatment site (e.g., AI frequently misses posterior rectal wall in the bladder-filling daily variation, over-extends bowel loops into the low pelvis on days with gas). Sites that implement Ethos or Elekta ONE adaptive therapy specifically recruit therapists with contouring confidence: this skill commands a salary premium.
AI is sitting alongside you hereMaintain treatment records and documentation in the electronic health record and R&V system, entering and updating patient treatment parameters, daily dose fractions delivered, IGRT image-match results and applied shifts, acute toxicity assessments, and patient communications in ARIA or Mosaiq
Maintain treatment records and documentation in the electronic health record and R&V system, entering and updating patient treatment parameters, daily dose fractions delivered, IGRT image-match results and applied shifts, acute toxicity assessments, and patient communications in ARIA or Mosaiq; ensuring documentation is complete and accurate before the next treatment fraction; participating in on-treatment verification chart rounds.[1],[9]
AI-assisted charting and automated plan check tools (ClearCheck) are absorbing the most repetitive documentation and verification tasks, automated tolerance checks flag parameter deviations that previously required manual spreadsheet review. Your documentation role is evolving toward clinical interpretation rather than data entry: the shift results still need human review, the toxicity assessment still needs clinical judgment, and the on-treatment chart round still needs a therapist who understands what changed in the patient's anatomy or response since simulation. Develop strong ARIA or Mosaiq proficiency (both are listed in the majority of 2025-2026 job postings) so you can navigate the system efficiently and spend your cognitive bandwidth on the clinical decisions rather than the software mechanics.
AI is sitting alongside you hereAssist with treatment planning and dosimetry procedures, participating in simulation CT setup (patient positioning, IV contrast coordination, 4D CT for respiratory-gated treatments, MRI fusion simulation), creating and placing reference marks and tattoos, entering treatment couch and isocenter coordinates into the TPS or R&V system
Assist with treatment planning and dosimetry procedures, participating in simulation CT setup (patient positioning, IV contrast coordination, 4D CT for respiratory-gated treatments, MRI fusion simulation), creating and placing reference marks and tattoos, entering treatment couch and isocenter coordinates into the TPS or R&V system; at sites with expanded therapist scope, reviewing auto-contoured organ-at-risk structure sets from tools like Limbus Contour or Mirada DLCExpert before physician approval.[10],[11]
AI auto-contouring tools are fundamentally changing what 'assist with treatment planning' means for the radiation therapist. At traditional sites, this was mostly administrative (coordinate entry, setup documentation). At AI-enabled centers, therapists increasingly contribute to OAR structure set review, checking that Limbus Contour or DLCExpert auto-generated contours meet departmental standards before the dosimetrist and oncologist finalize the plan. This scope expansion is both an opportunity and a responsibility: therapists who develop anatomical contouring literacy become contributors to the planning workflow, not just observers. Study your departmental contouring guidelines and RTOG/ESTRO consensus atlases for the treatment sites you simulate most frequently: this knowledge is now clinically actionable at the console.
Where radiation therapists go next
Natural next steps for someone with your foundation: not exits, evolutions.
- Medical and Health Services Managers
- US median pay
- $123,860 (May 2025)
- BLS outlook 2025-35
- +24.2%
- Medical Dosimetrists
- US median pay
- $147,470 (May 2025)
- BLS outlook 2025-35
- +5%
What each move takes
Medical and Health Services Managers
Experienced radiation therapists are natural candidates for radiation oncology department leadership roles: chief therapist, radiation oncology administrator, and cancer center operations director. These positions manage the clinical, operational, and regulatory aspects of a radiation therapy program, scheduling workflows, linac utilization optimization, staff credentialing (ARRT, JRCERT), NRC/state radiation license compliance, capital equipment planning, and vendor contract management. As AI tools (Ethos, Elekta Unity, SGRT) become standard infrastructure, administrators who understand the clinical and technical dimensions of these platforms are highly valued by health system leadership. A master's degree in health administration (MHA) or business administration (MBA) is the standard credential upgrade, combined with several years of clinical RT experience.
- · Health administration fundamentals: MHA or MBA with healthcare concentration, programs at UAB, Ohio State, and Tulane have strong radiation oncology industry connections; online programs allow concurrent clinical practice
- · Regulatory compliance: NRC materials license management, Agreement State radiation protection program requirements, Joint Commission standards for radiation oncology, CMS billing compliance for technical component RT services
- · Operational analytics: linac utilization metrics, patient throughput modeling, staffing ratios for adaptive vs. conventional treatment programs; familiarity with AI scheduling optimization tools increasingly expected at large centers
- · AI vendor management: evaluating proposals from Varian, Elekta, Accuray, Mevion, and emerging adaptive therapy vendors; building institutional business cases for Ethos, MR-linac, or SGRT investments; understanding total cost of ownership for AI-enabled linac programs
- · Quality improvement: ASTRO APEx accreditation standards, ACR radiation oncology practice standards, AAPM TG-142 and TG-275 compliance oversight, the administrative foundation for a safe and accredited RT department
How has the work of radiation therapists changed since 1896?
The tools that defined the work, one line per era. Select an era to see how it reshaped the work.
Orthovoltage X-ray therapy (Roentgen tube, 100-400 kV)
The earliest radiation therapy used orthovoltage X-ray machines: the same Crookes tubes and later Coolidge tubes that produced diagnostic X-rays, operated at higher voltages for longer exposures to deposit dose in tumors. The therapist of this era had no dosimetry badge, no real-time imaging, and no reliable way to measure the dose actually delivered. Positioning was by surface anatomy and experience. The skin absorbed a large fraction of the beam, limiting deep-tumor doses and producing severe skin reactions. Workers received cumulative lifetime doses orders of magnitude above today's occupational limits; the death toll among early radiotherapy practitioners was staggering.
Effect on the workNo systematic workforce counts exist for this era. Practitioners were recruited from nursing, general radiography, and physics; "radiation therapist" was not yet a distinct occupation. The toll on practitioners from unprotected radiation exposure is documented in "American Martyrs to Science Through the Roentgen Rays" (Percy Brown, 1936), which named radiographers and therapy workers who died from occupational radiation exposure.
Cobalt-60 teletherapy machine
The first clinical cobalt-60 treatments in North America were delivered in 1951 (London, Ontario and Saskatoon, Saskatchewan). For the radiation therapy worker, the cobalt era created the first truly specialized role: the machine required dedicated protocols, specific source-to-skin distance setup, shielding management, and formal training. The 1964 ARRT certification examination for radiation therapy technology was a direct response to the cobalt era's creation of a distinct, reproducible technical skill set. Cobalt machines also drove the JRCERT to establish formal accreditation for therapy programs in 1969-1971.
Effect on the workThe cobalt machine created the radiation therapist as a distinct allied health professional. The 1968 AMA/ACR/ASRT Essentials document governing program accreditation noted that "almost all technologists entering radiation therapy technology at that time were recruited from radiography and nursing," reflecting the cobalt era's need to formalize the workforce. Thousands of radiation therapy workers by the mid-1960s.
Medical linear accelerator (linac) with rotating gantry
Compact rotating-gantry linear accelerators were installed clinically in the early 1960s; by the 1970s the linac had overtaken cobalt as the dominant radiotherapy platform at academic centers, and by the 1980s it was the standard machine at most US hospitals with cancer programs. The linac produced higher-energy photon beams (several MV), offered multiple electron energies for superficial tumors, and gave the therapist a more controllable beam geometry. For the workforce, linac adoption expanded the technical scope: therapists now managed machine warm-up procedures, calibration checks, multi-field isocentric setups, and the record-and-verify (R&V) systems that tracked cumulative dose. The dual-energy linac with integrated electron mode became the Swiss Army knife of external beam therapy.
Effect on the workLinac adoption drove formal education standards higher and pushed the occupation toward an associate- or bachelor-degree entry requirement. The JRCERT expanded its accreditation scope; ASRT membership in all radiologic technology specialties grew from 14,000 in 1968 to 28,500 in 1994. Radiation therapy enrollment in accredited programs grew in parallel with linac deployment.
CT simulation and computer-based treatment planning
The introduction of dedicated CT simulators in the mid-1980s transformed radiation therapy planning from a 2D fluoroscopic process (the "conventional sim") into a 3D volume-based workflow. Instead of taking single-plane X-ray films to define treatment fields, therapists now acquired volumetric CT datasets at the simulation appointment, and dosimetrists used 3D treatment planning systems to compute dose distributions across the entire body volume. For the therapist, CT simulation added a new skill: setting up patients for a CT acquisition using reproducible immobilization devices (thermoplastic masks, custom molds) and marking the body surface with reference tattoos tied to the CT coordinate system. The simulation appointment became a foundational clinical encounter, not simply a field-drawing exercise.
Intensity-modulated radiation therapy (IMRT) and multileaf collimator (MLC)
The first commercial IMRT system, the MIMiC device, was used clinically in April 1994. Dynamic multileaf collimators (MLCs) built into the linac head allowed the beam cross-section to modulate in real time as the gantry rotated, sculpting high-dose regions around the tumor while sparing adjacent organs. IMRT required the therapist to understand and verify complex field arrangements with dozens of MLC leaf positions per arc, to operate new computer-controlled delivery systems, and to confirm that the machine's actual delivery matched the treatment planning calculation. IMRT also dramatically expanded the range of sites treated with curative intent: prostate, head and neck, and gynecologic cancers that had been difficult to treat without severe toxicity became routinely manageable. The IMRT era raised the technical floor for the profession.
Effect on the workIMRT adoption across US cancer centers from the late 1990s through the mid-2000s is one reason the radiation therapist workforce grew between 2000 and 2010: more complex treatments required more hands-on physicist and therapist time per patient, partially offsetting efficiency gains from computer planning.
Image-guided radiation therapy (IGRT): CBCT, kV/MV imaging, EPID
Image-guided radiation therapy added an on-board imaging step to every treatment fraction: before each treatment, the linac acquires a cone-beam CT (CBCT) or kV X-ray pair at the treatment position, the therapist performs an image match comparing the day's anatomy to the planning CT, and a couch shift is applied to align the target precisely. IGRT was enabled by on-board imaging systems that Varian and Elekta began integrating into clinical linacs in the early 2000s. For the therapist, IGRT created a new daily cognitive task: interpreting the image match, deciding whether the offset is within tolerance or requires escalation to the physicist or oncologist, and documenting the result. The shift from tattooing the patient and hoping they lay the same way every day to verifying anatomy daily with imaging was the most consequential workflow change in the profession since cobalt replaced orthovoltage.
Effect on the workIGRT extended the average treatment appointment time per fraction due to imaging and couch correction steps, which modestly increased staffing requirements per treatment vault. IGRT competency became a standard requirement in radiation therapist job postings through the 2000s and 2010s.
AI-driven online adaptive radiotherapy (Ethos, Elekta Unity MR-Linac, auto-contouring)
The Elekta Unity MR-Linac entered clinical use in 2018, integrating a 1.5T MRI with a linac for real-time soft-tissue imaging at the treatment position. Varian's Ethos adaptive therapy system followed in 2019 and received expanded FDA 510(k) clearance in 2024. These platforms use AI to auto-segment organs-at-risk and target volumes on the daily image, then generate a new optimized treatment plan adapted to the patient's anatomy that day, all within the treatment timeslot. For the radiation therapist, this is the most significant role shift in the profession's history: from executing a fixed plan that was designed at simulation to reviewing and approving AI-generated contours and plans in real time at the treatment console. The therapist becomes a clinical quality gate, not a plan executor. Surface-guided radiation therapy (AlignRT, C-RAD Catalyst), AI auto-contouring software (Limbus Contour, Mirada DLCExpert), and automated plan QA tools (Radformation ClearCheck) complete the AI toolkit reshaping daily practice.
Effect on the workAdaptive therapy centers specifically recruit and pay a premium for radiation therapists with on-console AI contour review skills. The PMC 11177026 Australasian study (2024) found radiation therapists surveyed are "generally optimistic" about AI: it reduces planning prep time while expanding expectations for on-console decision-making, patient-centered care, and AI model interpretability. The net workforce effect of adaptive therapy is more skilled practitioners per vault, not fewer.
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Browse all rolesRadiation Therapists employment and pay by year
View all 26 years of cited US data, each linked to its source
| Year | US employment | Annual pay (median unless marked) | Source | Report |
|---|---|---|---|---|
| 1964 | 3,000 | n/a | Est., Radiation Therapy Schools Researched context | Report |
| 1980 | 7,500 | n/a | Est., ASCO Post Researched context | Report |
| 2000 | 15,000 | n/a | Est., Sunbelt Staffing Researched context | Report |
| 2003 | 13,990 | $54,190 | BLS OEWS May 2003 Official statistic | Report |
| 2004 | 14,470 | $57,700 | BLS OEWS May 2004 Official statistic | Report |
| 2005 | 14,120 | $62,340 | BLS OEWS May 2005 Official statistic | Report |
| 2006 | 14,290 | $66,170 | BLS OEWS May 2006 Official statistic | Report |
| 2007 | 14,620 | $70,010 | BLS OEWS May 2007 Official statistic | Report |
| 2008 | 14,850 | $72,910 | BLS OEWS May 2008 Official statistic | Report |
| 2009 | 15,570 | $74,170 | BLS OEWS May 2009 Official statistic | Report |
| 2010 | 16,590 | $74,980 | BLS OEWS May 2010 Official statistic | Report |
| 2011 | 18,380 | $76,630 | BLS OEWS May 2011 Official statistic | Report |
| 2012 | 18,230 | $77,560 | BLS OEWS May 2012 Official statistic | Report |
| 2013 | 16,950 | $79,140 | BLS OEWS May 2013 Official statistic | Report |
| 2014 | 16,380 | $80,090 | BLS OEWS May 2014 Official statistic | Report |
| 2015 | 16,930 | $80,220 | BLS OEWS May 2015 Official statistic | Report |
| 2016 | 17,450 | $80,160 | BLS OEWS May 2016 Official statistic | Report |
| 2017 | 17,250 | $80,570 | BLS OEWS May 2017 Official statistic | Report |
| 2018 | 18,260 | $82,330 | BLS OEWS May 2018 Official statistic | Report |
| 2019 | 17,860 | $85,560 | BLS OEWS May 2019 Official statistic | Report |
| 2020 | 17,390 | $86,850 | BLS OEWS May 2020 Official statistic | Report |
| 2021 | 16,050 | $82,790 | BLS OEWS May 2021 Official statistic | Report |
| 2022 | 15,510 | $89,530 | BLS OEWS May 2022 Official statistic | Report |
| 2023 | 16,640 | $98,300 | BLS OEWS May 2023 Official statistic | Report |
| 2024 | 18,700 | $101,990 | BLS OEWS May 2024 Official statistic | Report |
| 2025 | 17,070 | $105,310 | BLS OEWS May 2025 Official statistic | Report |