MLS (ASCP) - Medical Laboratory Scientist

The American Society of Clinical Pathology (ASCP) grants the Medical Laboratory Specialist (MLS) certification to recognize healthcare professionals in medical laboratory science. A certified MLS conducts routine to complex laboratory tests in blood banking, chemistry, hematology, immunology, biology, and urinalysis to diagnose and treat diseases. MLS certification requires critical thinking skills to solve specimen, test, and instrumentation problems. Medical Laboratory Scientists work with physicians and other healthcare professionals to determine courses of action when treating patients.

Cost

• Exam Fee: $250

• International Candidate Fee: $250. There is a discount of $95 for applicants that have a medical laboratory education and reside in specific countries listed in the International Pricing Policy.

• Starting in January 2026, certification fees will increase by $10, with exceptions available for international candidates living in low-resource countries.

Test Format

The MLS (ASCP) examination is a timed (2.5 hours), computer-based exam with 100 multiple-choice questions. The ASCP Board of Certification (BOC) administers the MLS certification exam using the format of Computer Adaptive Testing (CAT). The CAT format measures knowledge and skills more accurately than standard fixed-form tests. Test takers can't skip items because the CAT algorithm measures the individual’s ability level for each question answered. Each exam adjusts to the test takers’ knowledge level, and every exam is unique. 

The exam content covers areas within Medical Laboratory Science, including blood banking, urinalysis, chemistry, hematology, immunology, and lab operations. Examinations are scored on a scale of 0 to 999, with a minimum passing score of 400.

Exam Results

The computer-based exam is scored electronically. Applicants receive Pass/Fail results immediately at exam completion. The ASCP BOC emails a detailed score report within 24 hours. Successful applicants receive their certificates in the mail within 3 to 5 weeks of passing the exam.

Steps to Obtain the MLS Certification

• Determine your exam category and eligibility route

• Log in or create an ASCP account

• Complete the online application

  • Upload appropriate documentation as PDF files within the online application

• Submit the non-refundable application fee within 90 days of starting application

• Request academic institution to send official transcripts to the ASCP BOC, if applicable

• Monitor application status by logging into ASCP account to View the Status

  • Applicants receive emails notifications when changes in status occur

• Resolve any deficiencies with the application

• Await Admission Notification email

• Schedule exam date with Pearson VUE

• Prepare for exam day

• Await official exam results

Eligibility Requirements: 

The American Society of Clinical Pathology offers five options to meet eligibility requirements:

1. Hold a Bachelor’s degree from a medical laboratory scientist program accredited by the National Accrediting Agency for Clinical Laboratory Sciences (NAACLS)

2. Certification as a medical laboratory technician, plus a bachelor’s degree from an accredited institution plus two years of full-time clinical lab experience

3. Hold a Bachelor’s degree plus five years of related work experience

4. Current ASCP medical technician (MT)/medical laboratory science (MLS) certification, plus a bachelor’s degree from a regionally-accredited college or university, plus five years of full-time clinical experience

5. Completion of a 50-week US military medical laboratory training course in the past ten years, plus a bachelor’s degree plus one year of full-time clinical experience

In 2023, the pathway to qualify through a Clinical Laboratory Assistant certification was officially phased out.

Once eligibility is met, candidates must apply for the certification exam. The application for MLS certification is completed online through an ASCP account. MLS candidates must submit the application fee within 90 days of the application start date.

Candidates who pass the exam receive a notification via email to view their exam score within four business days of completing the exam. They receive their wall certificates in approximately 3 to 5 weeks for U.S. mail and 6 to 9 weeks for International mail.

Candidates who are unsuccessful at passing the exam may reapply. They may retake the exam up to five times under the same eligibility route. If they fail five times under this route, they must meet the eligibility requirements under an alternate eligibility route. If they don't meet any of the alternate requirements, they're no longer eligible to apply for the MLS exam. Each time an applicant applies to take the MLS exam, they must pay the full $250 application fee.

Certified medical lab scientists must renew MLS certification every three years. MLS certification renewal requires 36 points in continuing education activities defined by the Credential Maintenance Program (CMP).

Renewal Fee

• Renewal fee: $100

• Reinstatement fee: $135

• Fee is reduced by $20 if renewing multiple ASCP certifications that expire on the same day or will expire in three months of each other.

• Starting in January 2026, renewal fees will increase by $10.

Effective 1/1/2023, all certification categories are required to complete one CMP point of continuing education in the area of medical ethics (e. g., HIPAA, compliance, confidentiality training.)

The ASCP offers the following resources for exam candidates, including:

• Content Outline

• Reading List

• Exam and Certification Procedures

• Review Course (Cost: $59 for non-members and $49 for members)

• Practice Exam (Cost: $99 for non-members and $89 for members)

• Study Guide and Review Course (Cost: $129 for non-members and $109 for members)

• Study Guide, Review Course and Practice Exam (Cost: $179 for non-members and $149 for members)

• Study Guide, Quick Compendium of Medical Laboratory Sciences 2e, Review Course and Practice Exam (Cost: $249 for non-members and $199 for members)

The ASCP offers other certifications, including:

• Technologist in Microbiology (M)

• Technologist in Molecular Biology (MB)

• Specialist in Chemistry (SC)

• Diplomate in Laboratory Management (DLM)

• Specialist in Blood Banking (SBB)

• Specialist in Molecular Biology (SMB)