Hepatitis B Surface Antigen Lab Test
Hepatitis B Surface Antigen Lab Test can be requested without a referral, and this overview covers what to expect. The Hepatitis B Surface Antigen (HBsAg) lab test checks your blood for a protein that appears on the surface of the hepatitis B virus. It is ordered to find out if you are currently infected with hepatitis B, which can be transmitted through blood, sex, or from mother to baby during birth.
- Sample type
- blood
- Category
- Sexual Health
- Turnaround
- 1-3 business days
- Price
- $24
- Referral
- Not required
The Hepatitis B Surface Antigen (HBsAg) lab test checks your blood for a protein that appears on the surface of the hepatitis B virus. It is ordered to find out if you are currently infected with hepatitis B, which can be transmitted through blood, sex, or from mother to baby during birth.
What it measures
- Hepatitis B surface antigen (HBsAg) — The main marker: if present, it means the virus is in your blood and you can pass it to others.
- Hepatitis B surface antibody (anti-HBs) — Often tested alongside HBsAg; a positive result usually means you are protected from hepatitis B, either from vaccination or past infection.
- Hepatitis B core antibody (anti-HBc) — Another marker that can show if you have ever been exposed to the virus, even if it is no longer active.
Who it is for
A doctor or clinic may order this test if you have symptoms like yellow skin or eyes, if you are pregnant, or if you have risk factors such as contact with an infected person or a history of sharing needles.
Preparation
No fasting or special preparation is needed for this blood test. You can eat and drink normally before your appointment.
Results and what they mean
Results are reported as positive (antigen found) or negative (not found), sometimes with a numerical value. A positive result usually means you have a current hepatitis B infection and may need further tests. Only a healthcare provider can interpret your results correctly; this information is not medical advice.
How to order this test
- Choose the test and place a confidential order online.
- Select a certified collection site and pick a time that suits you.
- Have your specimen collected — most draws take only a few minutes.
- Review results in a secure portal, typically within 1–3 days.
Preparation, hours, and pricing vary by site; confirm details directly with the lab before your visit.
Availability by state
Direct-access online ordering for the hepatitis b surface antigen lab test is available in most states. It is currently unavailable in 6 states:
Everywhere else you can order confidentially and collect your sample at a certified site. Browse by state →
Frequently asked questions
Is this test the same as a hepatitis B screening?
It is one part of hepatitis B screening. Screening often includes this test plus others to check for protection or past exposure.
Can I get hepatitis B from the test itself?
No. The test uses a small blood sample from your arm, and you cannot catch hepatitis B from the test.
What does a positive result mean for my partner?
A positive result means you can pass the virus to others. Your partner may need testing and vaccination, so talk with your doctor.
How long until I get results?
Most labs return results in 1 to 3 business days. Your doctor's office will contact you.