Chronic Kidney Disease Stages Explained (Stage 1 to 5)

Chronic Kidney Disease Stages Explained (Stage 1 to 5): eGFR ranges, symptoms, causes, and treatment options at every stage, backed by research.

Your kidneys filter about 150 quarts of blood every single day. Most people never think about that number until something goes wrong. Chronic kidney disease, or CKD, changes that filtering process slowly, often silently, and understanding the chronic kidney disease stages explained here can help you or someone you love catch the problem early enough to act.

This guide walks through all five stages of CKD in plain language: what each stage means, what the lab numbers actually tell you, what symptoms to watch for, and what you can do at every point along the way.

Key takeaways

• CKD has 5 stages, based mainly on a number called eGFR (estimated glomerular filtration rate).
• Stage 1 and Stage 2 CKD usually cause no symptoms. Blood and urine tests find them first.
• Stage 3 is where fatigue, swelling, and changes in urination often begin.
• Stage 4 means severe kidney damage and requires close medical supervision.
• Stage 5, also called kidney failure or end-stage renal disease (ESRD), typically requires dialysis or a transplant.
• CKD affects roughly 1 in 7 adults in the United States, and most don’t know they have it (Centers for Disease Control and Prevention [CDC], 2023).
• Diet, blood pressure control, and blood sugar management can slow CKD at almost every stage.

Introduction

Chronic kidney disease develops over months or years, not overnight. That’s the tricky part. Your kidneys can lose a large share of their function before you feel anything different. By the time symptoms show up, the disease has often already moved past the early stages.

This article breaks down the chronic kidney disease stages explained by stage number, from Stage 1 (mild, often unnoticed) to Stage 5 (kidney failure). You’ll learn the eGFR ranges doctors use, the warning signs at each level, and the treatment approach that fits each stage. Every claim about health outcomes here is backed by a cited source, listed in APA format at the end.

If you or a family member just received a CKD diagnosis, or you’re trying to understand a lab report with the word “eGFR” on it, this article is written for you.

What is chronic kidney disease?

Chronic kidney disease means your kidneys have been damaged, or are working below normal levels, for 3 months or longer (National Kidney Foundation [NKF], 2024). The kidneys’ main job is filtering waste and extra fluid out of your blood. When that filtering slows down, waste builds up in your body.

CKD is diagnosed and staged using two main measurements:

1. eGFR (estimated glomerular filtration rate): This estimates how much blood your kidneys filter per minute. A healthy eGFR sits around 90 or higher.
2. uACR (urine albumin-to-creatinine ratio): This checks for a protein called albumin in your urine. Healthy kidneys don’t leak much albumin. A high uACR is often the earliest sign of kidney damage, even when eGFR still looks normal (Kidney Disease: Improving Global Outcomes [KDIGO], 2024).

Doctors use both numbers together, not just one, to figure out how serious the damage is and how fast it might get worse.

How doctors stage chronic kidney disease?

The KDIGO guidelines, which most nephrologists follow worldwide, split CKD into stages labeled G1 through G5 based on eGFR, and further classify risk using albuminuria categories A1 to A3 (KDIGO, 2024). Here’s the eGFR breakdown in simple terms:

Stage	eGFR range (mL/min/1.73m²)	What it means
Stage 1	90 or above	Stage 1 Normal filtering, but signs of kidney damage present
Stage 2	60 to 89	Mild loss of kidney function
Stage 3a	45 to 59	Mild to moderate loss
Stage 3b	30 to 44	Moderate to severe loss
Stage 4	15 to 29	Severe loss of kidney function
Stage 5	Below 15	Kidney failure

Now let’s go through each one.

Stage 1 CKD: mild kidney damage, normal filtration

Stage 1 is the earliest point on the chronic kidney disease stages explained scale. Your eGFR sits at 90 or above, which is a normal filtering rate. So what makes it CKD at all?

The answer is damage markers. You might have protein in your urine, blood in your urine, or an imaging scan (like an ultrasound) showing an abnormal kidney structure. The filtering rate hasn’t dropped yet, but the tissue itself already shows signs of harm.

Common causes at Stage 1:

• Early diabetes-related kidney changes
• High blood pressure
• A family history of kidney disease
• Past kidney infections or inflammation

Symptoms: Almost none. This is exactly why Stage 1 is the most commonly missed stage. Most people feel completely fine.

What helps at this stage:

• Get blood pressure under 130/80 mmHg, the target most guidelines recommend for people with CKD and albuminuria (KDIGO, 2024)
• Manage blood sugar tightly if you have diabetes
• Cut back on sodium
• Stay hydrated, but don’t overdo fluid intake without medical guidance
• Avoid regular use of NSAIDs like ibuprofen, which can strain the kidneys over time

A 2021 study in the Journal of the American Society of Nephrology found that intensive blood pressure control reduced the risk of kidney function decline and cardiovascular events in adults with early CKD, compared to standard control (Cheung et al., 2021). Catching CKD at Stage 1 and acting on it gives you the best odds of protecting kidney function long-term.

Stage 2 CKD: mild loss of kidney function

At Stage 2, eGFR drops to somewhere between 60 and 89. Kidney function has declined slightly, but it’s still considered mild.

Symptoms: Still usually silent. Some people notice slightly more fatigue or mild swelling in the ankles, but many feel nothing unusual at all.

Risk factors that speed up progression from Stage 2:

• Uncontrolled diabetes
• Obesity
• Smoking
• High cholesterol
• Chronic use of certain medications

Management focus:

• Regular monitoring, typically every 6 to 12 months
• Continued blood pressure and blood sugar control
• A kidney-friendly diet lower in processed sodium and added sugar
• Weight management, since excess body weight is directly linked to faster CKD progression (Chang et al., 2019)

One important note: eGFR naturally declines somewhat with age. A 70-year-old with an eGFR of 65 and no other damage markers may not have the same risk profile as a 35-year-old with the same number. This is why doctors look at the whole picture, not a single lab value in isolation.

Stage 3 CKD: moderate loss, split into 3a and 3b

Stage 3 is where things usually start to feel different, and it’s split into two parts.

Stage 3a: eGFR between 45 and 59 Stage 3b: eGFR between 30 and 44

This is often the stage where a primary care doctor refers a patient to a nephrologist, a kidney specialist.

Symptoms that commonly appear at Stage 3:

• Fatigue and low energy
• Swelling in the feet, ankles, or hands
• Changes in urination: more frequent, less frequent, foamy, or darker urine
• Back pain near the kidney area
• Trouble sleeping
• Muscle cramps

What’s happening inside the body: As filtering slows, waste products like urea and creatinine build up in the blood. This can trigger anemia (because kidneys help produce a hormone called erythropoietin, which signals bone marrow to make red blood cells) and early bone health issues, since kidneys also help regulate calcium and phosphorus (NKF, 2024).

Treatment approach at Stage 3:

• Referral to a nephrologist
• Blood tests to check for anemia and bone mineral imbalances
• Possible medication adjustments, including SGLT2 inhibitors, which multiple randomized trials have shown slow CKD progression and reduce cardiovascular risk in patients with and without diabetes (Heerspink et al., 2020)
• A registered dietitian consultation to manage protein, potassium, and phosphorus intake
• Continued blood pressure control, usually with ACE inhibitors or ARBs, which protect kidney function by reducing pressure inside the filtering units (KDIGO, 2024)

A 2020 clinical trial published in the New England Journal of Medicine found that dapagliflozin, an SGLT2 inhibitor, reduced the risk of kidney function decline, kidney failure, or death from kidney or cardiovascular causes by 39% compared to placebo in patients with CKD (Heerspink et al., 2020). This kind of evidence has changed how doctors treat Stage 3 CKD over the past several years.

Stage 4 CKD: severe loss of kidney function

Stage 4 means eGFR has fallen to between 15 and 29. This is serious. Kidney function is significantly reduced, and the body starts struggling to manage waste, fluid balance, and hormone regulation on its own.

Symptoms often become harder to ignore:

• Persistent fatigue
• Swelling in the legs and around the eyes
• Nausea or loss of appetite
• Metallic taste in the mouth
• Muscle twitches or cramps
• Shortness of breath
• Difficulty concentrating
• Changes in skin color or itching

What happens medically at this stage: Doctors begin preparing patients for the possibility of kidney failure, even if it hasn’t arrived yet. This includes:

• Detailed discussion of treatment options: hemodialysis, peritoneal dialysis, or kidney transplant evaluation
• Vaccination updates (hepatitis B, for example, matters if dialysis becomes necessary)
• Access planning, such as creating a fistula for future dialysis, since this needs time to mature before use
• Nutrition counseling that’s more restrictive on potassium, phosphorus, and sometimes protein
• Managing complications like anemia, high blood pressure, and bone disease more aggressively

Emotional and practical support matters here too. A Stage 4 diagnosis is life-changing news. Research published in Kidney International Reports found that patients who received early, structured education about treatment options before reaching kidney failure had better outcomes and made more informed choices about their care path (Wong et al., 2018).

Stage 5 CKD: kidney failure (end-stage renal disease)

Stage 5 means eGFR has dropped below 15. This is kidney failure, also called end-stage renal disease (ESRD). At this point, the kidneys can no longer keep up with the body’s needs on their own.

Symptoms at Stage 5 are usually significant:

• Severe fatigue
• Significant swelling
• Little or no urination
• Nausea and vomiting
• Confusion or trouble concentrating
• Muscle cramps and weakness
• Itchy skin
• Shortness of breath, sometimes from fluid buildup around the lungs

Treatment options at Stage 5:

1. Hemodialysis: Blood is filtered by a machine, usually 3 times a week at a dialysis center or, for some patients, at home.
2. Peritoneal dialysis: A fluid is used inside the abdominal cavity to filter waste, often done daily at home.
3. Kidney transplant: A donor kidney, from a living or deceased donor, replaces the function of the failed kidneys. This generally offers the best long-term quality of life for eligible patients (United States Renal Data System [USRDS], 2023).
4. Conservative (non-dialysis) management: Some patients, particularly older adults with multiple health conditions, choose symptom-focused care instead of dialysis. This is a valid and increasingly recognized path, guided by a patient’s goals and values.

More than 808,000 people in the United States are living with ESRD, and about 68% of them are on dialysis while 32% are living with a kidney transplant (National Institute of Diabetes and Digestive and Kidney Diseases [NIDDK], 2024).

Chronic kidney disease stages explained: quick comparison

• Stage 1: eGFR 90+. Damage present, function normal. No symptoms in most cases.
• Stage 2: eGFR 60–89. Mild function loss. Rarely symptomatic.
• Stage 3a/3b: eGFR 30–59. Moderate loss. Fatigue, swelling, urination changes often begin.
• Stage 4: eGFR 15–29. Severe loss. Symptoms are usually noticeable and treatment planning intensifies.
• Stage 5: eGFR below 15. Kidney failure. Dialysis or transplant is typically needed.

Who is most at risk for CKD?

According to the CDC’s 2023 national report, roughly 1 in 7 adults in the United States, about 35.5 million people, have chronic kidney disease, and most don’t know it (CDC, 2023). The following groups carry higher risk:

• People with diabetes: about 1 in 3 adults with diabetes may have some degree of kidney disease (American Kidney Fund, 2024)
• People with high blood pressure: CKD prevalence reaches roughly 24.6% among adults with hypertension (NKF, 2024)
• Adults age 65 and older: CKD prevalence climbs to about 34% in this age group, compared to roughly 6% in adults 18 to 44 (NIDDK, 2024)
• People with a family history of kidney disease
• People with obesity
• Non-Hispanic Black adults, who face a CKD prevalence of about 20%, notably higher than other racial and ethnic groups tracked in national data (NIDDK, 2024)

Diet and lifestyle changes that support kidney health

Diet changes look different at each stage, and a registered dietitian who specializes in kidney disease can personalize this. Still, a few general principles apply broadly across early-to-moderate CKD:

• Limit sodium to help control blood pressure and reduce fluid retention. Most kidney-focused guidelines recommend under 2,300 mg per day, sometimes lower.
• Watch potassium and phosphorus intake in Stage 3 and beyond, since damaged kidneys struggle to clear these minerals. Bananas, oranges, potatoes, and dairy are common foods to moderate.
• Moderate protein intake at later stages, since protein breakdown creates waste the kidneys must filter. This should be guided by a professional, not self-directed, since too little protein causes its own problems.
• Stay active. Regular movement supports blood pressure control and blood sugar management, both of which protect kidney function.
• Quit smoking. Smoking accelerates kidney function decline and raises cardiovascular risk, which is already elevated in CKD patients (Chang et al., 2019).
• Limit alcohol and stay consistent with prescribed medications.

When should you see a doctor?

Don’t wait for symptoms. Because early CKD is often silent, testing matters more than how you feel day to day. Talk to a doctor about kidney function testing if you have:

• Diabetes or prediabetes
• High blood pressure
• A family history of kidney disease
• Unexplained swelling in your legs, ankles, or face
• Foamy or bloody urine
• Persistent fatigue with no clear cause
• Age 60 or older with other risk factors present

A simple blood test (for eGFR) and urine test (for uACR) can catch CKD early, when treatment has the strongest chance of slowing or stopping progression.

Conclusion

Understanding the chronic kidney disease stages explained from Stage 1 through Stage 5 gives you a real tool: the ability to recognize where you or a loved one stands, and what steps matter most at that point. Early stages offer the widest window for action, through blood pressure control, blood sugar management, and lifestyle changes. Later stages call for closer medical supervision and, eventually, a decision about dialysis or transplant.

CKD is common, serious, and often quiet in its early years. But it’s also manageable, especially when caught early and treated with the right combination of medical care and daily habits. If any part of this article applies to you, the most useful next step is simple: ask your doctor for an eGFR and uACR test.

Disclaimer

This article is for general educational purposes only and does not replace professional medical advice, diagnosis, or treatment. Chronic kidney disease staging, symptoms, and treatment plans vary by individual. Always consult a licensed physician or nephrologist about your specific health condition, test results, and treatment options before making medical decisions.

References

American Kidney Fund. (2024). Quick kidney disease facts and stats. https://www.kidneyfund.org/all-about-kidneys/quick-kidney-disease-facts-and-stats

Centers for Disease Control and Prevention. (2023). Chronic kidney disease in the United States, 2023. U.S. Department of Health and Human Services. https://www.cdc.gov/kidney-disease/php/data-research/index.html

Chang, A. R., Grams, M. E., & Navaneethan, S. D. (2019). Bariatric surgery and kidney-related outcomes. Kidney International Reports, 4(4), 511–517. https://doi.org/10.1016/j.ekir.2018.12.013

Cheung, A. K., Rahman, M., Reboussin, D. M., et al. (2021). Effects of intensive BP control in CKD. Journal of the American Society of Nephrology, 32(4), 926–937. https://doi.org/10.1681/ASN.2020101486

Heerspink, H. J. L., Stefánsson, B. V., Correa-Rotter, R., et al. (2020). Dapagliflozin in patients with chronic kidney disease. New England Journal of Medicine, 383(15), 1436–1446. https://doi.org/10.1056/NEJMoa2024816

Kidney Disease: Improving Global Outcomes. (2024). KDIGO 2024 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney International, 105(4S), S117–S314. https://kdigo.org/wp-content/uploads/2024/03/KDIGO-2024-CKD-Guideline.pdf

National Institute of Diabetes and Digestive and Kidney Diseases. (2024). Kidney disease statistics for the United States. National Institutes of Health. https://www.niddk.nih.gov/health-information/health-statistics/kidney-disease

National Kidney Foundation. (2024). Kidney disease: Fact sheet. https://www.kidney.org/about/kidney-disease-fact-sheet

United States Renal Data System. (2023). 2023 USRDS annual data report: Epidemiology of kidney disease in the United States. National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health. https://usrds-adr.niddk.nih.gov/2023

Wong, S. P. Y., Hebert, P. L., Laundry, R. J., et al. (2018). Decisions about renal replacement therapy in patients with advanced kidney disease. Kidney International Reports, 3(6), 1252–1262. https://doi.org/10.1016/j.ekir.2018.07.001