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The stages of kidney disease, explained
✓ Fact-checked against sourced references · Editorial standards
Kidney disease is staged using the estimated glomerular filtration rate (eGFR), worked out from blood creatinine, age and sex. The stage tells how much filtering capacity remains and guides how closely it is watched.
The five stages
| Stage | eGFR | What it means |
|---|---|---|
| G1 | 90+ | Normal filtering, with other signs of damage |
| G2 | 60–89 | Mildly reduced filtering |
| G3a / G3b | 30–59 | Moderate reduction |
| G4 | 15–29 | Severe reduction |
| G5 | Below 15 | Kidney failure |
Why urine protein matters too
The amount of protein in the urine is a separate risk marker, so a complete picture needs both the eGFR and a urine albumin result.
Frequently asked questions
What does stage 3 kidney disease mean?
Moderate reduction in filtering (eGFR 30–59). Care focuses on slowing progression and treating complications.
Sources
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Educational only. This guide is general kidney-care information, not individual medical advice.