What Does an eGFR of 30 Mean?
Medically reviewed by Dr. Rishi Kumar Kafle, MBBS, MD, FASN · Last reviewed June 2026
An eGFR of 30 mL/min/1.73m² falls in CKD stage G3b (moderate–severe decrease). Filtration is moderately reduced; many medications need dose adjustment in this range.
Where 30 Sits on the CKD Scale
The KDIGO GFR categories run from G1 to G5: G1 ≥90, G2 60–89, G3a 45–59, G3b 30–44, G4 15–29, and G5 below 15. An eGFR of 30 is in the G3b band. A value under 60 sustained for three months indicates chronic kidney disease.
What an eGFR of 30 Does and Does Not Tell You
eGFR estimates how much blood the glomeruli filter each minute, indexed to a standard body size of 1.73m². A single value of 30 is a snapshot: it can dip temporarily with dehydration, a recent heavy meal of cooked meat, or an acute illness, then recover. That is why chronic kidney disease is defined by an eGFR under 60 that persists for at least three months, ideally alongside a urine albumin-to-creatinine ratio. eGFR is also least precise near the normal range, so a result of 30 should be confirmed and trended rather than treated as a fixed score. It does not, on its own, explain why filtration is at this level — that needs the clinical context, the trend, and other tests.
What to Do Next
- Confirm whether the value is stable and check albuminuria (uACR), which refines the risk picture.
- Review medications that need adjustment when filtration falls, and avoid nephrotoxins where possible.
- Manage the common drivers — blood pressure and blood glucose — that most often lower eGFR over time.
- Discuss the result with your clinician in the context of your age and overall health.
How an eGFR of 30 Is Confirmed
One eGFR is rarely the whole story. Laboratories calculate it from a single serum creatinine using the race-free CKD-EPI 2021 equation, so anything that moves creatinine moves the estimate. To confirm a result of 30, a clinician typically repeats the blood test, looks at the trend over months rather than a single day, and adds a urine albumin-to-creatinine ratio — because kidney damage can be present at a near-normal eGFR and absent at a mildly reduced one. Where creatinine is unreliable, for example in people with very high or very low muscle mass, a cystatin C estimate can confirm the figure independently of muscle.
When to Seek Care
An eGFR of 30 that is confirmed and persistent should be reviewed by your clinician, who will check albuminuria, blood pressure, and your medication list, and arrange follow-up. Seek timely advice for swelling, a marked drop in urine output, or new breathlessness, and have your kidney function rechecked before and after any test using contrast dye.
For drug dosing, your clinician will use a creatinine clearance rather than eGFR — see CrCl vs eGFR.