The Serum Albumin test is a common blood test that measures the amount of albumin in the liquid portion of your blood (serum). Albumin is the most abundant of the plasma proteins and is made primarily by the liver. It has two major jobs: it helps keep fluid in your bloodstream by maintaining osmotic pressure, and it acts as a carrier protein that transports hormones, vitamins, minerals, and many medications through the body.

Your result is typically reported in grams per deciliter (g/dL). In plain language, low serum albumin often suggests your body is not making enough albumin, losing it, or that it is “diluted” by excess fluid. This can be seen with liver function problems (reduced production), certain kidney health issues (loss of albumin in urine), inflammation or serious illness (albumin shifts during illness), malabsorption or poor nutritional status, and fluid overload. High serum albumin is less common and is most often related to dehydration (less plasma water makes albumin appear higher). Your clinician interprets the value in context with symptoms and other labs such as total protein, liver enzymes, kidney tests, urine protein, and markers of inflammation as part of a broader health assessment and disease diagnosis.

Serum albumin is often ordered as part of a comprehensive metabolic panel (CMP) or liver panel, or as a stand-alone test when a clinician needs insight into liver function, kidney health, overall protein status, or fluid balance. It is also used to monitor chronic conditions and recovery from illness.

Your doctor may order a serum albumin blood test if you have symptoms or findings such as:

• Swelling in the legs, ankles, feet, or around the eyes (edema)
• Abdominal swelling or fluid buildup (ascites)
• Unexplained weight loss, poor appetite, or concerns about malnutrition
• Persistent fatigue, weakness, or frailty
• Foamy urine or known protein in the urine (possible kidney protein loss)
• Jaundice (yellow skin/eyes), dark urine, or other signs of liver disease
• Long-standing digestive symptoms (chronic diarrhea, suspected malabsorption)

It may also be checked if you have risk factors or clinical situations such as chronic liver disease (including alcohol-related disease or viral hepatitis), diabetes or high blood pressure with kidney risk, chronic inflammatory conditions, major infection, cancer, severe burns, hospitalization/critical illness, or before/after major surgery to help evaluate baseline protein status and recovery.

• Chronic liver disease (including cirrhosis)
• Hepatitis (viral or autoimmune)
• Nephrotic syndrome and other protein-losing kidney diseases
• Chronic kidney disease (in certain contexts)
• Protein-losing enteropathy (loss of protein through the intestines)
• Malnutrition and severe undernourishment
• Malabsorption disorders (e.g., celiac disease)
• Chronic inflammation or severe infection (systemic illness)
• Heart failure or fluid overload states (may lower measured albumin via dilution)
• Severe burns or major trauma (protein loss and inflammatory changes)

• Monitoring liver function and progression of known liver disease
• Supporting kidney health evaluation when protein loss is suspected (often paired with urine albumin/protein tests)
• Assessing nutritional status and protein adequacy during weight loss, frailty, or chronic illness
• Evaluating fluid balance and causes of swelling (edema/ascites)
• General wellness and baseline health assessment as part of routine blood work (e.g., CMP)
• Monitoring recovery after surgery, hospitalization, or serious infection/inflammation
• Helping guide overall disease diagnosis when symptoms suggest liver, kidney, or systemic illness