200+ Free ASCP MLS Practice Questions
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Key Facts: ASCP MLS Exam
100
Exam Questions
ASCP BOC MLS exam page
2h 30m
Exam Time
ASCP BOC MLS exam page
400
Minimum Passing Score
ASCP 100-999 scoring scale
$260
Application Fee
ASCP BOC MLS exam page
2025-09-25
Guideline Revision
ASCP MLS content guideline
351,200
US Lab Jobs (2024)
BLS
ASCP BOC lists the MLS exam as 100 questions in 2 hours 30 minutes with scores reported on a 100-999 scale and 400 as the minimum passing score. The current MLS application fee is $260, and ASCP's MLS content guideline was revised on September 25, 2025. BLS reports 351,200 clinical laboratory technologist/technician jobs in 2024 with a median annual wage of $61,890.
About the ASCP MLS Exam
The ASCP MLS exam certifies entry-level medical laboratory scientists in blood banking, chemistry, hematology, microbiology, urinalysis/body fluids, immunology, and laboratory operations. ASCP exams are delivered at Pearson VUE test centers.
Questions
100 scored questions
Time Limit
2 hours 30 minutes
Passing Score
Scaled score 400 (100-999)
Exam Fee
$260 (ASCP BOC / Pearson VUE)
ASCP MLS Exam Content Outline
Blood Banking
ABO/Rh, antibody identification, compatibility testing, components, and transfusion reactions
Chemistry
Electrolytes, renal/liver markers, acid-base interpretation, calculations, and quality control
Hematology
CBC interpretation, morphology, coagulation studies, and hematologic disorders
Microbiology
Specimen processing, organism identification, media, AST/QC, and rapid diagnostic methods
Laboratory Operations
CLIA compliance, quality management, instrumentation, safety, and critical-result workflows
Urinalysis & Body Fluids
Chemical and microscopic urinalysis plus CSF, synovial, and serous-fluid interpretation
Immunology
Autoimmune testing, infectious serology algorithms, and immunoglobulin/complement interpretation
How to Pass the ASCP MLS Exam
What You Need to Know
- Passing score: Scaled score 400 (100-999)
- Exam length: 100 questions
- Time limit: 2 hours 30 minutes
- Exam fee: $260
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
ASCP MLS Study Tips from Top Performers
Frequently Asked Questions
How many questions are on the ASCP MLS exam?
ASCP BOC lists the MLS exam at 100 questions with a 2 hour 30 minute testing time. Questions are multiple choice and mapped to the MLS content guideline domains.
What score do I need to pass ASCP MLS?
ASCP reports exam scores on a 100-999 scale. The minimum passing score is 400.
What topics are tested on ASCP MLS?
The MLS guideline domains are Blood Banking (17-22%), Chemistry (17-22%), Hematology (15-20%), Microbiology (17-22%), plus Laboratory Operations, Urinalysis/Body Fluids, and Immunology (each 5-10%).
How much is the ASCP MLS exam fee in 2026?
The current ASCP BOC MLS application fee is $260 (non-refundable) on the ASCP MLS exam page.
How should I study for ASCP MLS?
Use blueprint-weighted prep: 1) prioritize blood bank, chemistry, microbiology, and hematology first, 2) run daily mixed sets with calculations and interpretation, 3) review missed questions by domain, and 4) practice timing for a 2 hour 30 minute session.
Do MLS eligibility routes change over time?
Yes. ASCP route requirements are updated periodically (for example, ASCP notes Route 3 is no longer available as of January 1, 2023). Always verify your exact route on the current ASCP BOC MLS page before applying.