Part of Achilles tendinopathy
Achilles tendonitis or plantar fasciitis? Sorting out heel pain
Warning signs, and when to get help
Where does it hurt?
Four structures crowd into one heel, and they occupy different surfaces of it. Work out which surface is sore and you have done most of the sorting.
The underside, toward the inner edge, belongs to the plantar fascia, the thick band that runs along the sole and attaches to the bottom of the heel bone. Tenderness there, together with the typical first-step pattern, is the pair of findings used to identify it: localized tenderness on the inner part of the heel bone plus morning first-step pain that eases after a short walk (Chang and colleagues, 2022). The underside of the heel is also the subject of its own US physical therapy clinical practice guideline, which covers heel pain and plantar fasciitis, not the tendon at the back (Koc and colleagues, 2023). You cannot reach it from the back of the heel and you cannot reach the Achilles from underneath, which is why the pressing test is more use than any description of how the pain feels.
The cord above the heel belongs to the Achilles tendon, in the region Silbernagel and colleagues (2020) describe as 2 to 6 cm above where it attaches. You can pinch this part between thumb and finger. If squeezing the rope makes you wince, that is your answer.
The bone at the very back of the heel is the Achilles insertion, where the tendon fans onto the bone. AAOS OrthoInfo describes insertional pain as sitting at the lower part of the tendon at the back of the heel, and notes that bone spurs often form there.
The soft spot just in front of the tendon, between it and the bone, holds a small fluid-filled cushion called the retrocalcaneal bursa. The NHS lists bursitis among the causes of heel pain, with redness, swelling and a dull ache in the heel.
One test covers all four. Sit with the sore foot across the other knee, and in turn press the underside of the heel toward the inside, pinch the cord, press the hard back edge of the heel, and press just in front of the tendon on either side of it. Then ask which of those made you pull your foot away. Nothing here is a diagnosis, and it is the same starting point a clinician uses.
How do Achilles tendonitis and plantar fasciitis feel different?
Plantar fasciitis is a standing and walking problem. The pattern is pain that is worst on the first steps of the day and eases after a short walk (Chang and colleagues, 2022), and the NHS describes pain between the arch and the heel that feels worse when you start walking and better when you rest. It tends to come back when you stand up after sitting, and again after a long day on your feet. Barefoot on a hard floor is the worst version of it. People tend to describe it as sharp or like a stone bruise under the heel.
Achilles pain is a push-off problem. It is at its worst going up stairs or hills, accelerating, standing on tiptoe to reach a shelf, and at the end of a run rather than at the start. People describe stiffness as much as pain, and the tendon often feels thickened. The Guy's and St Thomas' leaflet lists being overweight, tight or weak calf muscles, a stiff ankle and a sudden increase in activity among the contributors.
Where they are not different is the morning, because both are sore first thing. OrthoInfo lists pain and stiffness along the Achilles in the morning among the usual symptoms, and the Guy's leaflet says it is common to have pain when you get up or when you start walking after a rest. The morning pattern gets treated as the deciding clue, and it is not. Heel pain in the morning goes through that pattern and what else produces it.
One more test, and it costs nothing: stand on tiptoe on the sore leg. If that is the move that hurts, you are loading the Achilles. If standing flat with your weight into the heel is what hurts, you are loading the fascia.
What about the back of the heel: bursitis, a bone spur or the tendon?
Several structures share the same half inch, and the labels for them blur into one another. The tendon insertion is one. Another is a bony prominence on the upper back part of the heel bone, which Choo and colleagues (2020) describe as a Haglund deformity, and the bone spurs that OrthoInfo says often form at the back of the heel with insertional tendinitis sit in the same place. So does the bursa in front of the tendon, which the NHS names with its redness, swelling and dull ache.
Syed and Perera (2016) describe Haglund's syndrome as covering the deformity, insertional tendinopathy and bursitis together. So these are frequently a package rather than alternatives, and the ones that come with visible swelling or a prominence you can feel are the ones most likely to be more than tendon alone. Redness and heat change things, though: a hot, red, swollen heel, or heel pain with a fever, is on the warning list on this page with a same-day timing, because infection looks like this too.
There is no separate page on this site for retrocalcaneal bursitis or Haglund deformity, so this short section is the whole of what we have on them. Insertional or midportion Achilles tendinopathy is the page for the tendon side of this spot and for why the handling differs.
Can you have both at once?
The fascia and the tendon attach to opposite ends of the same bone, and they are loaded by the same walking and standing. They react to the same changes: a new job on your feet, a jump in running, a holiday spent in flat sandals, a long spell of being much less active followed by a sudden return. Having both at once is common, and it would be strange if they never turned up together.
We are not giving a figure for how often, because we have no study of it to cite and a made-up percentage is worse than none. The shape of the mixed picture is the useful part. Usually one problem leads and the other grumbles, and the second one only becomes obvious once the first improves. So people finish a course of treatment feeling half better and conclude it did not work, when what has actually happened is that the louder problem has quietened down.
If both spots are tender, say both at your appointment rather than choosing the one that fits what you read. And apply the cautious rule from the Achilles side: with tenderness at the insertion, leave below-step heel drops out until a clinician says otherwise.
Does it change what you should do?
What they share is the bulk of it. Calf loading is part of both, and each condition has a US physical therapy guideline that puts loading in the program: tendon loading at loads as high as tolerated for midportion Achilles tendinopathy, on strong evidence (Chimenti and colleagues, 2024), and resistance training for the muscles of the foot and ankle for plantar heel pain, on moderate evidence (Koc and colleagues, 2023). The NHS self-care advice for heel pain includes regular gentle stretching, and the calf stretch is a reasonable place to start for the fascia. Footwear matters for both: something with a soft sole and a little heel rather than nothing on your feet on a hard floor. So does cutting the load before adding exercises, and judging any change by the next morning rather than by how it feels at the time.
Calf stretching that pulls the ankle up hard, and letting the heel drop below a step, are the moves to leave out if the Achilles insertion is the sore part, and neither is a problem for the fascia. Loading aimed at the fascia itself, including the plantar fascia stretch, belongs to plantar heel pain and is not part of an Achilles program. The heel lift that eases an irritated Achilles insertion is not the same intervention as a cushioned insole for a sore fascia either, even when the object in the shoe looks similar.
For the programs themselves, the Achilles tendinopathy program and the plantar fasciitis program set out the staged exercises for each. If you have both, work from the more restrictive set of the two until someone has assessed you.
What else causes heel pain that is neither?
A few other things produce heel pain, and the urgency differs between them. Heel pain in a growing child or teenager is usually centered on the growth plate at the back of the heel bone rather than on the fascia or the tendon, and it is the most common cause of heel pain in children (Kothari and colleagues, 2023). Other causes, including infection, do occur at that age. Sever's disease is written for parents. A child's heel needs looking at before any exercise program, and the children's line on the warning list says which symptoms cannot wait.
Two sore heels with no training explanation, especially alongside back stiffness that is worse in the morning, swollen joints elsewhere, psoriasis or a bowel condition, points toward an inflammatory arthritis such as ankylosing spondylitis rather than a load problem. That line on the warning list gives it a week or two.
A stress injury of the heel bone builds with walking instead of easing, and the heel hurts when squeezed from both sides at once, usually after a jump in training or a new job on your feet. Stress fractures come from repeated load rather than one injury (OrthoInfo), and the warning list gives the squeeze test its own entry with a timing, including the point that an early X-ray can look normal.
Nerve pain reads differently: burning, tingling, an electric quality, or a patch of sole that feels dead, carrying on at rest and at night rather than easing with movement. The nerve can be squeezed at the inner ankle, which is tarsal tunnel syndrome, although the evidence base for diagnosing and treating it is weak and much of the literature is opinion (Doneddu and colleagues, 2017).
The heel pad itself is the one most people have never heard of. Under the heel bone sits a pad of fat working as a shock absorber. A scoping review of heel fat pad syndrome traces that pattern to a single piece of work, a look back through the records of 250 people with heel pain at one hospital foot clinic in South Korea: pain that worsened the longer someone stood, pain at night and pain in both heels each made a fat pad problem much more likely, while morning first-step pain and tenderness at the inner heel bone made it much less likely (Chang and colleagues, 2022).
The reviewers do not take it at face value, and nor should you. They point out that those odds were reported without confidence intervals and without adjusting for age, sex or body weight, and that they found only seven original studies on the condition in total, calling the literature sparse. So treat that list as a hint, not a test, and note what it is comparing: two ordinary causes of heel pain, not heel pain against something sinister. It is no reason to put night pain down to the fat pad and leave it there, because heel pain at night or at rest that keeps getting worse has its own line and its own timing on the warning list.
And one that is not heel pain at all but gets confused with it: a sudden pop or snap at the back of the ankle, with push-off suddenly weak, is a possible Achilles tendon rupture and is the first line on the warning list.
When to see a physio or doctor
See a physio (physical therapist) or doctor if the pain is severe, stops you walking normally, keeps getting worse, or has not improved after a few weeks of looking after it yourself. The NHS suggests seeing a doctor if heel pain has not improved after 2 weeks of self-care, and sooner if it is severe, stopping you doing normal things, or coming with tingling or numbness. It also names diabetes on its own as a reason to see a doctor about heel pain, because foot problems can be more serious with diabetes, and the diabetes lines on the warning list below say what cannot wait.
An examination settles this quickly, which is the best argument for having one. Expect the clinician to press each of the spots described above, squeeze the heel from both sides, check how far your ankle bends up, watch you walk and ask what changed in the weeks before it started. Which surface of the heel you can put a finger on, and what you were doing differently in the month before it began, are the two answers that save the most time. The warning signs below each carry their own timing, and those come ahead of any routine appointment.
Related exercise programs
Warning signs
Get emergency help now
- You felt a sudden pop or snap at the back of your ankle, it felt as if someone hit or kicked you in the calf, or walking or rising onto your toes on that leg suddenly became weak or difficult. Stop exercising and go to an urgent care center or emergency department the same day, even if you can still walk, as this can be a torn (ruptured) Achilles tendon. This page does not cover a rupture.
Get help now, day or night
- Your tendon pain or swelling started while you were taking a fluoroquinolone antibiotic, such as ciprofloxacin or levofloxacin, or in the months after a course. Contact your doctor straight away. The UK medicines regulator (MHRA) advises stopping the antibiotic at the first sign of tendon pain or swelling and talking to your doctor. Hold off the calf exercises until you have been checked.
Get help today
- You felt a sudden pop or tearing under the foot, followed by bruising and difficulty walking. Stop the exercises, keep your weight off that foot as much as you can, and get it checked the same day.
- A calf or thigh that is newly swollen or getting more swollen, warm, tender, red or darker than usual, has swollen veins that are sore to touch, or has a throbbing or cramping pain that does not fit your injury or condition, or that feels different from normal muscle soreness after exercise. This can be a sign of a blood clot (deep vein thrombosis), especially after surgery, an injury, time in a cast or boot, a long trip or a spell of being much less mobile than usual. Get medical advice the same day. If you are also short of breath or have chest pain, call emergency services.
- The tendon or heel is hot, red and swollen, or you have a fever or feel unwell. Get medical help the same day, and go to an emergency department if you feel very unwell. If you have a very high or very low temperature, shivering you cannot control, you are breathing very fast or finding it hard to breathe, you are confused or your speech is slurred, your skin, lips or tongue look blue, gray, pale or blotchy (on brown or black skin this can be easier to see on the palms of the hands or soles of the feet), or you have a rash that does not fade when you press it, call emergency services, as this can be sepsis.
- The pain started with a fall or a blow to the back of the ankle, and there is bruising or you cannot put weight on the foot. Get it checked the same day.
- Same day: you have diabetes or numb feet, and one foot becomes hot, swollen or red, or changes color or shape, with or without pain. Take your weight off that foot straight away and get advice the same day from your doctor or your diabetes foot team. This can be Charcot foot, where the bones and joints of the foot are damaged and the foot can collapse. Do not exercise that foot until it has been checked. If you also have a fever or feel very unwell, or redness is spreading up your foot or leg, go to an emergency department.
- Same day: you have diabetes or numb feet and find a new blister, cut or sore on your foot, especially one you did not feel, a wound that smells or is leaking, or new pain in your foot that you cannot explain. Get it seen by your doctor or foot team the same day. If you also have a fever or feel very unwell, redness is spreading up your foot or leg, or part of your foot or a toe turns black, go to an emergency department.
- Same day: a burn, a scald or a blister on your foot or lower leg from hot water, a hot floor or pavement, a hot water bottle, an electric blanket, a heat pad, or sitting with your feet near a fire or radiator. Keep your weight off that foot and get it seen by your doctor or foot team the same day, however small the mark looks and even if it does not hurt. A foot that cannot feel heat can be burned deeply before you notice, and a burn on a numb foot can turn into an ulcer. If you also have a fever or feel very unwell, redness is spreading up your foot or leg, or part of your foot or a toe turns black, go to an emergency department.
- Heel pain in a child or teenager needs a doctor or physio to look at it before they start any exercises. See a doctor the same day, urgently, if your child is limping when they have not been playing sport, has pain in the hip, groin, thigh or knee as well as the heel, or has heel pain with a fever or seems unwell. If they cannot put weight on the leg, have a high temperature or seem very unwell, go to an emergency department. See a doctor within a day or two if pain wakes your child at night, pain at rest keeps getting worse, or there is a lump or swelling on the heel or ankle that keeps growing. Ask for an urgent appointment rather than the next routine one, and say what the pain does at night and whether a lump is getting bigger.
- The pain is there at night or at rest as well as with activity and keeps getting worse. If you are being treated for cancer now, contact your cancer team the same day.
Book an appointment
- The whole heel hurts when you squeeze it from both sides, especially after a sudden increase in running or walking, or if you have thin bones (osteoporosis). Stop running and jumping, cut down on walking and standing, and see a doctor within a few days, as this can be a stress fracture of the heel bone rather than plantar fasciitis. An X-ray can look normal for the first 2 to 3 weeks, so a normal early X-ray does not rule it out.
- Your heel or Achilles pain comes with back pain and stiffness that is worse in the morning and at night, or with painful, swollen joints elsewhere, or both heels became painful without an obvious reason. The same applies if you also have psoriasis, Crohn's disease or ulcerative colitis, or have had a red, painful, inflamed eye (iritis). This is not an emergency, but see your doctor in the next week or two, as it can be a sign of an inflammatory arthritis such as ankylosing spondylitis.
- You have numbness, tingling, burning or loss of feeling in the foot. Book an assessment with a doctor or physio in the next week or two. If it came on over hours or days, started after an injury, is spreading, or comes with weakness in the foot, get medical advice the same day.
- The pain is there at night or at rest as well as with activity and keeps getting worse. If you have had cancer, now or in the past, or are losing weight without trying, see your doctor sooner, within a day or two, and mention it. This applies even if the pain is not getting worse.
- The pain is there at night or at rest as well as with activity and keeps getting worse. See your doctor within a few days.
- With diabetes, get any new foot pain checked by your doctor before you start these exercises.
Common questions
How do I know if I have Achilles tendonitis or plantar fasciitis?
Press the two places and see which one objects. Sit down, cross the sore foot over the other knee, and press firmly into the underside of the heel toward the inner edge. Then press the back of the heel and pinch the cord of the tendon above it. Plantar fasciitis is tender underneath, and the clinical definition used in the research is exactly that pair of findings: tenderness on the inner part of the heel bone plus morning first-step heel pain that eases after a short walk (Chang and colleagues, 2022). Achilles pain is tender at the back. If the underside is fine and the back is sore, the fascia is not your problem, whatever the morning pattern looks like.
Can you have Achilles tendonitis and plantar fasciitis at the same time?
Yes, and in clinic it is a familiar combination. Both attach to the same heel bone, both are load problems, and the things that bring one on, a jump in walking or running, long days standing, new or very flat shoes, are the same things that bring on the other. We are not going to put a percentage on how often they occur together, because we have no source that studied it. What matters practically is that treating one and ignoring the other leaves you half better, which is a common reason people think a program failed.
Can Achilles tendonitis cause plantar fasciitis?
There is no source we can cite that shows one causes the other, so we will not claim it. What is fair to say is that they share contributors and sit at the same end of the same bone. Tight or weak calf muscles appear among the contributors to both: the Guy's and St Thomas' NHS leaflet lists tight or weak calf muscles and a stiff ankle for Achilles tendinopathy, and the NHS self-care advice for heel pain includes regular gentle stretching. Shared causes and shared treatment are not the same as one causing the other.
Is it Achilles tendonitis or bursitis at the back of the heel?
It can be difficult to separate by feel, and it often does not change the first moves. The retrocalcaneal bursa is a small fluid-filled cushion sitting between the tendon and the heel bone, and the NHS lists bursitis among the causes of heel pain, with redness, swelling and a dull ache. Syed and Perera (2016) describe Haglund's syndrome as covering a bony prominence at the back of the heel, insertional tendinopathy and bursitis together, which tells you how closely packed these are. Either way, the pressure comes off the back of the heel first.
Does the morning pain pattern tell them apart?
Not on its own, and this is the single most common reason people get stuck. Plantar fasciitis is classically worst on the first steps out of bed, and the NHS describes pain between the arch and the heel that feels worse when you start walking and better when resting. Achilles pain also brings morning stiffness: AAOS OrthoInfo lists pain and stiffness along the tendon in the morning among the usual symptoms, and the Guy's and St Thomas' leaflet says it is common to have pain when you get up in the morning or when you start to walk after resting. Two problems with the same timetable, so use location instead.
Does it matter which one it is, if the exercises are similar?
It matters for two specific decisions. The first is whether the heel may drop below a step: with pain at the insertion of the Achilles that is the move to leave out, and for plantar fasciitis it is not the issue. The second is whether you add loading aimed at the fascia itself, which belongs to a plantar heel pain program alongside the calf work and is not part of an Achilles program. The shared ground is calf loading and footwear, so plenty of what you do overlaps. The differences are small and they are the ones that make a program either work or hurt.
References
- Koc TA Jr, Bise CG, Neville C, et al. Heel Pain - Plantar Fasciitis: Revision 2023. Journal of Orthopaedic and Sports Physical Therapy. 2023;53(12):CPG1-CPG39. https://doi.org/10.2519/jospt.2023.0303
- Chimenti RL, Neville C, Houck J, Cuddeford T, Carreira D, Martin RL. Achilles Pain, Stiffness, and Muscle Power Deficits: Midportion Achilles Tendinopathy Revision - 2024. Journal of Orthopaedic and Sports Physical Therapy. 2024;54(12):CPG1-CPG32. https://doi.org/10.2519/jospt.2024.0302
- Silbernagel KG, Hanlon S, Sprague A. Current Clinical Concepts: Conservative Management of Achilles Tendinopathy. Journal of Athletic Training. 2020;55(5):438-447. https://doi.org/10.4085/1062-6050-356-19
- Chang AH, Rasmussen SZ, Jensen AE, Sorensen T, Rathleff MS. What do we actually know about a common cause of plantar heel pain? A scoping review of heel fat pad syndrome. Journal of Foot and Ankle Research. 2022;15:60. https://doi.org/10.1186/s13047-022-00568-x
- Syed TA, Perera A. A Proposed Staging Classification for Minimally Invasive Management of Haglund's Syndrome With Percutaneous and Endoscopic Surgery. Foot and Ankle Clinics. 2016;21(3):641-664. https://doi.org/10.1016/j.fcl.2016.04.004
- Choo YJ, Park CH, Chang MC. Rearfoot disorders and conservative treatment: a narrative review. Annals of Palliative Medicine. 2020;9(5):3546-3552. https://doi.org/10.21037/apm-20-446
- Kothari EA, Padgett AM, Young SM, Ray J, Shah A, Conklin MJ. A Review of Pediatric Heel Pain. Cureus. 2023;15(1):e34228. https://doi.org/10.7759/cureus.34228
- Doneddu PE, Coraci D, Loreti C, Piccinini G, Padua L. Tarsal tunnel syndrome: still more opinions than evidence. Status of the art. Neurological Sciences. 2017;38(10):1735-1739. https://doi.org/10.1007/s10072-017-3039-x
- American Academy of Orthopaedic Surgeons. Achilles tendinitis. OrthoInfo. https://www.orthoinfo.org/en/diseases--conditions/achilles-tendinitis/
- American Academy of Orthopaedic Surgeons. Stress fractures. OrthoInfo. https://www.orthoinfo.org/en/diseases--conditions/stress-fractures/
- Guy's and St Thomas' NHS Foundation Trust. Achilles tendinopathy. Patient information, resource number 4609/VER3. Last reviewed October 2024. https://www.guysandstthomas.nhs.uk/health-information/achilles-tendinopathy
- NHS. Heel pain. Page last reviewed 24 October 2025. https://www.nhs.uk/symptoms/foot-pain/heel-pain/
- National Institute for Health and Care Excellence. Diabetic foot problems: prevention and management. NICE guideline NG19. Published 26 August 2015, last updated 11 October 2019. https://www.nice.org.uk/guidance/ng19
- Medicines and Healthcare products Regulatory Agency. Fluoroquinolone antibiotics: must now only be prescribed when other commonly recommended antibiotics are inappropriate. Drug Safety Update. 22 January 2024. https://www.gov.uk/drug-safety-update/fluoroquinolone-antibiotics-must-now-only-be-prescribed-when-other-commonly-recommended-antibiotics-are-inappropriate
- NHS. Deep vein thrombosis (DVT). Page last reviewed 30 April 2026. https://www.nhs.uk/conditions/deep-vein-thrombosis-dvt/
- NHS. Symptoms: Ankylosing spondylitis. Page last reviewed 5 January 2023. https://www.nhs.uk/conditions/ankylosing-spondylitis/symptoms/
Written and checked by the PocketPhysio editorial team. Last updated 2026-10-21.
This page is general education, not a diagnosis or a personal treatment plan. See a physiotherapist or doctor for advice about your own situation.