How Often Can You Safely Have an X-ray?
There is no fixed legal limit on how many X-rays you can have in a year. Every scan must be clinically justified, meaning the benefit of getting a clear answer outweighs the very small radiation risk. The real question is not "how many," but whether each X-ray is the right investigation for you at that time.
Key takeaways
- There is no annual cap on how many X-rays are safe for patients in the UK.
- Every X-ray must be justified, meaning the clinical benefit must outweigh the risk.
- Radiation dose varies hugely between scan types. A chest X-ray delivers far less than a CT scan.
- Low dose systems like EOS use about 90% less radiation than a standard X-ray, around ten times less.
- Keeping a record of your imaging history helps your clinicians make better decisions.
Is there an X-ray limit per year?
No. UK regulations under IRMER (Ionising Radiation (Medical Exposure) Regulations) do not set a maximum number of X-rays a patient can receive in any time period. Annual dose limits exist for radiation workers, but those limits do not apply to patients having diagnostic scans.
Instead, the law places responsibility on the referrer and the practitioner. Every imaging request must meet the principle of justification: the expected benefit to you must outweigh the small risk from radiation. If a scan is justified, it is safe to go ahead, even if you have had several X-rays recently.
This surprises many people. The common belief that you are "only allowed a certain number per year" is a myth. What actually protects you is the requirement that no X-ray should ever be done without a good clinical reason.
What actually keeps repeated X-rays safe?
Two principles work together: justification and optimisation (often called ALARA, meaning "as low as reasonably achievable").
Every scan needs a clear clinical question. Your referrer decides whether the expected information justifies the exposure.
Once justified, the radiographer uses the lowest dose that still produces a diagnostic-quality image. Better technology means lower doses.
Keeping a record of past scans helps your clinicians avoid unnecessary repeats and track your cumulative exposure over time.
In practice, this means a well-justified series of X-rays carries very little additional risk. The dose from a single diagnostic X-ray is extremely small compared to the natural background radiation you receive every day from the environment.
How much radiation does an X-ray give compared to other scans?
Radiation dose varies significantly between different types of imaging. The table below gives a general sense of scale. Effective dose is measured in millisieverts (mSv), a unit that accounts for how sensitive different body tissues are to radiation.
As you can see, a single chest or limb X-ray delivers a tiny fraction of the radiation you receive naturally each year. Even a lumbar spine X-ray is well below your annual background dose. CT scans deliver substantially more, which is one reason clinicians consider carefully before requesting them.
How does low dose imaging reduce your cumulative exposure?
Low dose imaging systems are designed to capture the same diagnostic information using about 90% less radiation than a standard X-ray, around ten times less. This is especially useful when you need standing, weight-bearing images of the whole body, because it means you can get a detailed alignment assessment with a very small dose.
At ScanAlign, low dose standing imaging, we use EOS technology. EOS captures full-length standing images of your skeleton from head to feet in a single pass. Because it uses so little radiation, it is well suited to follow-up imaging where you may need more than one scan over time, for example before and after a procedure. You can read more about EOS scan safety and radiation or explore whether an EOS scan is safe for your situation.
A note about MRI. EOS shows bones, joints and whole-body alignment. For soft tissue, discs or nerves, MRI is usually the better tool. MRI uses no radiation at all. Your clinician can advise which investigation is most appropriate for your question.
If you need standing whole-body imaging with very low radiation, we can help. Our free video consultation lets you discuss your imaging needs before committing.
Book a free video consultationWhat happens when you book a low dose scan at ScanAlign?
You do not need a GP referral. You can self-refer as a private, self-pay patient. Here is what to expect.
Free video consultation
A short call to understand your symptoms, review any previous imaging and confirm whether an EOS scan is the right next step.
Attend your scan
You stand naturally inside the EOS machine at 19 Harley Street. The scan takes around 15 to 20 seconds and uses about 90% less radiation than a standard X-ray.
Receive your report
A specialist radiologist analyses your images and produces a detailed report on your alignment. You receive this directly.
Share with your clinician
Your report can be shared with any treating clinician, surgeon or physiotherapist to guide your next steps.
ScanAlign also offers paediatric imaging at ScanAlign for younger patients who may benefit from the lowest possible dose. If you would like to book a low dose scan, the process starts with a free video call.
Frequently asked questions about X-ray safety
There is no maximum number set by UK law for patients. Each X-ray must be clinically justified. If every scan has a clear purpose, the cumulative risk remains very low.
No. Annual dose limits apply to radiation workers, not to patients undergoing diagnostic scans. For patients, the guiding principle is justification, not a numerical cap.
Yes, provided each scan is justified. For example, monitoring how a fracture is healing may require several X-rays. Each one helps your clinician make decisions, and the dose per image is very small.
ALARA stands for "as low as reasonably achievable." It means radiographers use the lowest dose that still gives a useful, diagnostic-quality image. Modern equipment and techniques make this increasingly effective.
It depends on the body area. A chest X-ray is roughly 0.02 mSv, equivalent to a few hours of natural background radiation. A lumbar spine X-ray is higher, at around 0.7 mSv, still well below what you receive naturally in a year.
Yes. EOS uses about 90% less radiation than a standard X-ray, around ten times less. This is especially helpful for full-body or spinal imaging where the area being scanned is large.
No. ScanAlign accepts self-referrals. You book a free video consultation first to discuss your symptoms and confirm that an EOS scan is appropriate for you.
It is a good idea. While there is no legal requirement for patients to track their own imaging, having a list of past scans helps any new clinician decide whether further imaging is needed or whether existing images can answer the question.
Diagnostic X-rays carry a very small theoretical risk. For a single examination, the additional risk is tiny compared to the natural lifetime risk of cancer. That is why justification matters: the clinical benefit should always outweigh this very small risk.
ScanAlign is a private, self-pay clinic. Pricing details are available on the website. The first step is always a free video consultation, which costs nothing.
Concerned about radiation from repeated imaging?
Talk to us. Our free video consultation helps you understand whether a low dose standing scan is right for your situation.
Book a free video consultationSources
- UK Health Security Agency (formerly PHE), "Ionising Radiation: Dose Comparisons," ukhsa.gov.uk
- The Ionising Radiation (Medical Exposure) Regulations 2017 (IR(ME)R), legislation.gov.uk
- European Society of Radiology, "EOS imaging system: a review of the literature," Insights into Imaging, 2019
Written by Abbas Dhami (Specialist Diagnostic Radiographer)
This page is general information and not a diagnosis.
ScanAlign is the trading name of CoreMed Solutions Ltd and operates under The Harley Street Hospital's CQC licence.