Most states do not have official regulations or guidelines regarding the practice of phlebotomy, with the exception of California. The California State Department of Public Health requires phlebotomists to attend a formal training program, gain considerable on-the-job experience and pass a certifying exam. The states offers three levels of phlebotomy certification to qualified applicants: Limited Phlebotomy Technician, Certified Phlebotomy Technician I and Certified Phlebotomy Technician II.

Obtain a high school diploma or GED certificate. Students pursuing a career in phlebotomy should complete coursework in biology, chemistry, physics, algebra, geometry, English and computer science. Students are also advised to learn a foreign language; phlebotomists work with patients from a plethora of nationalities and ethnic backgrounds.

Earn a phlebotomy technician I certification. This requires attending a phlebotomy technician training program approved by the Department of Public Health. Programs must provide students with a minimum 20 hours of basic classes and 20 hours of advanced classes; applicants with more than 1,040 hours of on-the-job experience only have to fulfill the advanced class requirement. Following graduation, candidates must successfully perform 50 venipunctures and 10 skin punctures on actual patients and pass a written phlebotomy exam.

Complete 20 additional hours of advanced classes at a phlebotomy training program approved by the Department of Public Health. As an admissions prerequisite, applicants will have to submit proof of being a Certified Phlebotomy Technician I, with a minimum 1,040 hours of on-the-job experience. During the program, students must successfully complete 20 arterial punctures under the supervision of a licensed Medical Doctor (MD), Physician Assistant (PA), Registered Nurse (RN), Clinical Laboratory Bioanalyst (CLB), Clinical Laboratory Scientist (CLS) or a Respiratory Care Practitioner (RCP).

Pass a written phlebotomy exam from a state-approved certifying organization. For exam eligibility, applicants must submit a certificate of completion from their training program.

Apply for Phlebotomy Technician II certification through the Department of Health Services. Along with the completed application, applicants must submit a $54 fee, as well as two current passport-sized photos. Candidates must also provide the following supporting documentation: official high school transcripts or a GED certificate, certificate of completion from a phlebotomy technician training program, proof of passing a certification exam and documentation verifying the successful completion of 50 venipunctures, 10 skin punctures and 20 arterial punctures.