Lean Six Sigma training
RecommendedIASSC recommends training from a qualified institution, Lean Six Sigma trainer or corporate program.
IASSC Certified Lean Six Sigma Black Belt (ICBB)
Validates advanced knowledge of the DMAIC method, including regression, designed experiments and statistical tools for Lean Six Sigma.
Summary
The IASSC Certified Lean Six Sigma Black Belt (ICBB) is a closed-book, proctored exam on the full DMAIC method. It is set at an advanced statistical level, and the certification stays current for three years and renews with a shorter exam.
Good fit if
- You want a Black Belt exam without ASQ’s project affidavits
- You are comfortable with regression and designed experiments
- You want an exam you can schedule online anytime
Look elsewhere if
- You want ASQ’s name after leading projects: CSSBB
- You are new to Lean Six Sigma: IASSC Green Belt
- Your goal is general project management: PMP
Salary & jobs
Prerequisites
Cost
What holders say
Employers ask about the project
Commenters say a legitimate Black Belt requires a significant project and presentation, and informed hiring managers ask about the project. An ASQ holder chose that route for its project requirement.
Carries less weight without a project
One holder earned the IASSC Black Belt to pad a résumé, and says it never came up in interviews and carries little weight without a project.
Depends on how you already work
A Black Belt adds depth in tools, statistics and coaching. If you are not already using Green Belt tools, another belt will not change much.
Certification path
IASSC’s Lean Six Sigma exams run Yellow, Green and Black Belt in rising scope.
Renewal
ICBB is Current for 3 years. Renew with a shorter closed-book exam.
- Validity
- 3 years
- Renewal requirement
- Recertification exam, 75 questions in 2 hours
- Renewal fee
- $335 USD
You need 70% to pass. Take it before your Current status ends or within 90 days after; you get two attempts, at least two weeks apart. If you do not recertify, the status becomes Elapsed and you must pass the full exam again to be Current.
IASSC recertification policy ↗Alternatives
FAQ
How much does the IASSC Black Belt exam cost?
$516 for the exam voucher. A retake needs a new voucher.
Do I need a project or experience for the IASSC Black Belt?
No. IASSC requires no project, training, experience or Green Belt. It recommends training and some real-world experience.
Is the IASSC Black Belt exam open book?
No. It is a closed-book, proctored exam of 150 questions in 4 hours, and you need 70% to pass.
Does the IASSC Black Belt expire?
IASSC recognizes the certification perpetually but shows it as Current for three years. Recertify with a 75-question exam ($335) to keep it Current.
Can I take the IASSC Black Belt online?
Yes. You can schedule an online proctored exam at any time, or use a test centre or accredited provider.
What is the difference between IASSC and ASQ Black Belt?
IASSC is a closed-book exam with no prerequisites and renews every three years. ASQ’s CSSBB is open book, requires signed project affidavits and renews every three years.
Last updated October 2026