- Fasting and prep
- No fasting needed. Follow the instructions on your lab order.
- Turnaround
- Usually 1 to 3 days.
- Also called
- anti-hbs, hbsab, hepatitis b surface antibody, hep b titer, hepatitis b titer
What it measures
Your body makes anti-HBs after the hepatitis B vaccine or after recovering from infection. Levels often fall over the years after vaccination, yet most people who once reached 10 mIU/mL stay protected because their immune memory remains. A core antibody (anti-HBc) test tells vaccine immunity apart from past infection.
Who should consider it
- Health care workers and students, 1 to 2 months after finishing the vaccine series
- Partners and household members of someone with hepatitis B
- People on dialysis or with weakened immune systems
- Babies born to parents with hepatitis B, at the time their pediatrician advises
- Adults unsure whether they were vaccinated
How to read your result
The CDC uses 10 mIU/mL or higher as the protective level. Values can run far above 100. Lab ranges and units differ, so use the cutoff printed on your report.
- 10 mIU/mL or higher means you are considered immune, per CDC.
- Below 10 after a full vaccine series may mean you did not respond, or that levels faded with time. A clinician may suggest a booster dose and a repeat test.
- A positive anti-HBs alone does not show whether immunity came from the vaccine or past infection. The core antibody test answers that.
- This test does not check for current infection. The surface antigen (HBsAg) test does.
Reference ranges differ between labs. Use the range printed on your own report.
What to do next
If your level is below 10 mIU/mL and you have no record of vaccination, talk with a clinician about the vaccine series. If you finished a series long ago, many clinicians give one booster and recheck. Health care workers should follow CDC and employer protocols, which spell out testing after each step.
Where to order Hepatitis B immunity test
These sellers include an independent physician order. You pay online and visit a partner lab. Availability, price, and lab network vary, so confirm at checkout.
Private MD Labs
Online lab seller- Order
- Every order reviewed by a physician. Says you pay $1 to start and the rest after results.
- Results
- Secure online portal with plain-English explanations. Says many results arrive overnight.
HealthLabs
Online lab seller- Order
- Online or by phone. No doctor referral or insurance needed.
- Results
- Secure HealthLabs account. Says 1 to 3 business days.
Walk-In Lab
Online lab seller- Order
- Online, no insurance or doctor order needed. Shows a $6 physician fee per order on popular tests.
- Results
- Online account. Turnaround not stated on its homepage.
Quest Health
Lab-run- Order
- Buy online and book a Quest appointment. An independent provider is involved.
- Results
- Online as soon as ready, with an email alert. Provider discussion included at no extra cost.
Seller details come from each seller's own site and can change. Confirm price, lab location, and state availability at checkout.
Ordering several tests? Plan them together · Filter all sellers
Questions people ask
What hepatitis B titer level means I am immune?
The CDC uses 10 mIU/mL or higher as protective. Some labs report only positive or negative, so a quantitative test shows the actual number.
My titer is low years after vaccination. Am I unprotected?
Not necessarily. Most people who responded to the vaccine keep immune memory even after antibody levels fade. A clinician can give a booster and recheck if your job requires proof.
Does a positive surface antibody mean I had hepatitis B?
It can come from the vaccine or past infection. A core antibody test shows which.
Can I order a hepatitis B titer without a doctor?
Yes. Online sellers include a physician order and a blood draw. Look for a quantitative test if your school or employer needs a number.
Related tests
- Hepatitis B surface antigenShows whether you currently have a hepatitis B infection.
- Measles, mumps, and rubellaChecks for protective antibodies to measles, mumps, and rubella.
- ChickenpoxChecks for antibodies that protect against chickenpox.
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