Medically reviewed for current US clinical guidance · Last reviewed: September 7, 2026
The classic sign of a kidney stone is sudden, severe pain in your side and back, just below the ribs, that can spread to the lower belly and groin and come in waves. Other common symptoms include blood in the urine, painful or frequent urination, cloudy or foul-smelling urine, and nausea. Small stones can sometimes pass with little or no pain. Where the pain is felt often shifts as the stone moves down the urinary tract.
| Symptom | What it feels like | Notes |
|---|---|---|
| Flank pain (renal colic) | Sharp, severe pain in the side and back below the ribs that comes in waves | The most common symptom; waves last minutes to hours |
| Pain that moves | Radiates to the lower abdomen and groin as the stone travels | Location shifts as the stone moves down the ureter |
| Blood in urine | Pink, red, or brown urine | Common; caused by the stone irritating the urinary tract |
| Urinary changes | Painful urination, urgency, frequent urination, cloudy or foul-smelling urine | More noticeable as the stone nears the bladder |
| Nausea and vomiting | Feeling sick with the pain | The nerves of the kidney and stomach are linked |
| Fever and chills | Feeling feverish with the pain | A warning sign of infection; seek care right away |
Where Kidney Stone Pain Starts and Moves
Kidney stone pain usually begins in the flank, the area of your side and back just below the ribs, on the side of the affected kidney. As the stone moves down the ureter toward the bladder, the pain often travels to the lower abdomen and groin. The pain typically comes in waves and can be intense enough to make it hard to sit still. This wave-like pain is called renal colic.
Symptoms by Stone Size
Small stones may move through the urinary tract and pass in the urine with little or no pain. Larger stones are more likely to get stuck, block urine flow, and cause the severe pain and other symptoms above. A stone that blocks the flow of urine, or that comes with fever, is more urgent.
Red-Flag Symptoms: Seek Care Right Away
Get medical care promptly, or go to the emergency room, if you have:
- Fever and chills with the pain, which can signal an infection in a blocked urinary system and is an emergency
- Pain so severe you cannot sit still or find comfort
- Nausea and vomiting that will not stop
- Blood in the urine
- Trouble passing urine, or being unable to urinate
Frequently Asked Questions
Where does kidney stone pain usually start?
It usually starts in the flank, the side and back just below the ribs, on the side of the affected kidney, and can spread to the lower abdomen and groin as the stone moves.
How long does kidney stone pain last?
Pain often comes in waves that last from a few minutes to hours. A small stone may pass within days to weeks; a stone that is stuck or causing infection needs medical treatment.
Is blood in the urine normal with a kidney stone?
Blood in the urine is a common symptom because the stone irritates the urinary tract. Still, tell your doctor about it so the cause can be confirmed.
When should I go to the emergency room?
Go right away for fever and chills with the pain, pain you cannot control, constant vomiting, or being unable to urinate. Fever with a suspected stone can mean a serious infection.
Can a kidney stone pass without symptoms?
Yes. Small stones can pass in the urine with little or no pain. Larger stones are more likely to cause the severe symptoms described here.
Related Reading on Know Your Surgery
- Kidney Stone Removal: Overview, Types, and What to Expect
- Kidney Stone Removal: Causes, Diagnosis, and When to Consider Surgery
- Kidney Stone Removal: Procedure, Recovery, and Rehabilitation
- Kidney Stone Removal: FAQs, Statistics, and Patient Stories
Sources
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH. Kidney stones symptoms and causes. https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-stones/symptoms-causes
- Urology Care Foundation (American Urological Association). Kidney stones. https://www.urologyhealth.org/urology-a-z/k/kidney-stones
- National Kidney Foundation. Kidney stones. https://www.kidney.org/kidney-topics/kidney-stones
- NIH MedlinePlus. Kidney stones. https://medlineplus.gov/kidneystones.html
Medical Disclaimer
This article is for general education and reflects typical US patterns. Symptoms vary, and other conditions can cause similar pain. Seek prompt care for fever with pain, severe or uncontrolled pain, constant vomiting, or trouble urinating. This article is not medical advice.