Mary Sean O'Halloran, LP
Mary Sean O'Halloran is a Psychologist based in Longmont, CO with over 37 years of clinical experience. Medicare-enrolled per CMS records and offers virtual telehealth visits.
Patients across CO can see Mary Sean O'Halloran, LP in person in Longmont or via virtual visit — no travel required. With 37+ years of experience, she has been practicing in the Longmont area. A psychologist is an individual who is licensed to practice psychology which is defined as the observation, description.
Older · 1707dNPPES updated 2021-09-20 · verify NPI on CMS · Verify license at Colorado Medical Board
Contact & Location
Practice Location
1751 Hover St Ste B4, Longmont, CO 80501-7181
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Background & Specialty
Education, training, and specialty classification from CMS NPPES and Medicare records.
Board certified · Sep 19, 2021
Self-reported via NPPES
37 years in practice
Senior practitioner
A psychologist is an individual who is licensed to practice psychology which is defined as the observation, description, evaluation, interpretation, and modification of human behavior by the application of psychological principles, methods, and procedures, for the purpose of preventing or eliminating symptomatic, maladaptive, or undesired behavior and of enhancing interpersonal relationships, work and life adjustment, personal effectiveness, behavioral health, and mental health. The practice of psychology includes, but is not limited to, psychological testing and the evaluation or assessment of personal characteristics, such as intelligence, personality, abilities, interests, aptitudes, and neuropsychological functioning; counseling, psychoanalysis, psychotherapy, hypnosis, biofeedback, and behavior analysis and therapy; diagnosis and treatment of mental and emotional disorder or disability, alcoholism and substance abuse, disorders of habit or conduct, as well as of the psychological aspects of physical illness, accident, injury, or disability; and psycheducational evaluation, therapy, remediation, and consultation. Psychological services may be rendered to individuals, families, groups and the public.
Taxonomy: 103T00000X
Mailing address
525 Bowen St, Longmont, CO 80501-5333
Differs from practice location
Virtual Psychology Care With Mary Sean O'Halloran
NPPES records indicate this provider offers telehealth services. Contact the office to confirm availability and scheduling.
Schedule a virtual visit with Mary Sean O'Halloran for follow-ups, medication reviews, and ongoing care — no travel to Longmont required. The office sends a secure video link before your appointment. Most visits take 15–30 minutes. Medicare enrolled per CMS records.
Frequently Asked Questions
Common questions about Mary Sean O'Halloran
Dr. O'Halloran is listed as active in the NPI registry with telehealth listed in Longmont, CO. NPI status alone doesn't confirm open availability — call the office to confirm. Phone: (720) 635-0755.
Sourced from CMS NPPES · OIG LEIE. See Data Methodology.
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Contact Mary Sean O'Halloran
Practice Location
1751 Hover St Ste B4, Longmont, CO 80501-7181
Mailing Address
525 Bowen St, Longmont, CO 80501-5333
This is a provider directory. Contact the office directly to schedule appointments.
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