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Northwell Health Mather Hospital Port Jefferson

On Long Island, Northwell Health Mather Hospital Port Jefferson operates a daytime program for severe psychiatric symptoms. Its listing indicates a typical stay of 7 days and nine kinds of therapy. The care fits people who need structure but not overnight stays.

  • Joint Commission
  • Outpatient
  • Co-Occurring Mental Health
  • 7 days

This Port Jefferson site is a hospital-based behavioral health program, and its partial hospitalization track is meant for adults and adolescents whose psychiatric symptoms are serious but who can safely return home in the evening. The clinical team addresses mental health conditions together with related substance use concerns, so a person is not asked to split their care into two unrelated tracks.

Days are full and structured, five days a week, and the plan is written with input from the person in treatment, their family and the physician who referred them. Staff keep crisis coverage available at every hour of the day, all week, which gives families a place to turn between sessions. This hospital-based treatment in Port Jefferson works as either a step down from inpatient care or a way to avoid hospitalization.

Hospital settings come with more paperwork and a more clinical pace than a stand-alone rehab. That structure tends to suit someone who wants a defined daytime routine and a medical campus close by. For Long Island residents weighing a structured day program against standard outpatient services, this center lists co-occurring mental health treatment alongside outpatient care.

If it is unclear whether partial hospitalization offers the intensity you need, the helpline is no cost and can help you compare it with other options and learn what your insurance covers. Trained advisors connect callers with licensed treatment providers. There is no cost, and nothing is required of you.

Treatment tracks and care levels

At the heart of this center's services is a partial hospitalization program, a structured level of care designed for individuals who do not require 24-hour inpatient care but need more support than a weekly outpatient visit can offer. The program operates Monday through Friday, and the typical length listed is 7 days; however, your actual duration will depend on your clinical needs and insurance review. Many people looking for inpatient rehab on Long Island find this listing early, so it is useful to understand that this is a day program, not a residential rehab.

Counseling choices cover one-on-one sessions, group counseling cognitive behavioral therapy family counseling dialectical behavior therapy, relapse prevention counseling twelve step facilitation online therapy and trauma specific therapy. Teenagers get tutoring so schoolwork keeps pace. Continuing support can come through an intensive outpatient program, outpatient treatment, a recovery coach or support meetings. For people across Long Island, this Port Jefferson center lists co-occurring mental health services and outpatient treatment.

Approaches listed include family involvement, individual treatment and Twelve Step work. Specializations include day treatment, personality disorders and post traumatic stress disorder. If a clinician believes a different level of care is warranted, then that conversation should happen before admission rather than after.

  • Relapse Prevention Counseling
  • 1-on-1 Counseling
  • Twelve Step
  • Group Therapy
  • Trauma-Specific Therapy
  • Individual Treatment
  • Family Therapy
  • Online Therapy
  • Cognitive Behavioral Therapy
  • Dialectical Behavior Therapy

Who this hospital program is built for

  • Adults and adolescents with serious psychiatric symptoms who need daily structure
  • Children, teens, young adults, older adults, men and women
  • People dealing with mental health and substance use disorders at once
  • Individuals stepping down from inpatient care or trying to prevent a hospital stay
  • People living with depression, anxiety, bipolar disorder, trauma or personality disorders
  • Anyone dealing with chronic relapse, drug use concerns or smoking cessation

Rooms, daily schedule and languages

Attendees join daytime groups Monday through Friday, then go home each evening. The listing indicates a usual stay of 7 days, tutoring lets adolescents keep up with their classes, and clinicians offer crisis response around the clock, every day of the week. Care is offered in English. If you need a different language, ask before booking an intake, since the listing names only one. The Joint Commission accredits this center, a detail worth confirming by phone when you inquire about a specific level of care.

Cost of care and insurance checks

The listing notes cash pay rates as a private payment choice, though no price for a full course of treatment appears here. Insurance is verified by phone before admission, so have your plan details ready and ask what your share would be at a partial hospitalization level of care. If you reach out to the helpline instead, a trained advisor can check availability and coverage at no cost, and nothing requires you to go forward. If your plan will not cover this program, asking early about other rehabs and centers on Long Island keeps things moving.

Things to clarify before you enroll

  • Does my insurance cover this partial hospitalization program, and what will I owe?
  • What determines the 7-day length, and what if I need additional time?
  • Who writes the treatment plan, and how much say do I and my family have?
  • What crisis support is available on evenings and weekends?
  • If I have both a mental health and a substance use diagnosis, how are the two treated together?
  • Is tutoring available for my adolescent, and how is schoolwork coordinated?
Paperwork and a cup of tea on a table

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Long Island, New York at dusk
Family support

Good to know

What is Northwell Health Mather Hospital Port Jefferson known for?

The listing describes a hospital-based behavioral health program that provides a partial hospitalization level of care for adults and adolescents and holds Joint Commission accreditation. Nine therapy options, treatment for mental health conditions that occur alongside addiction and a typical program length of 7 days are shown, with sessions five days a week and crisis coverage at all hours.

Does this program treat substance use along with mental health?

Yes. The listing names co-occurring disorders, chronic relapse, drug use concerns and smoking cessation among the issues treated, alongside depression, anxiety, trauma and personality disorders. Someone with both a mental health and a substance use diagnosis gets one coordinated plan rather than two separate tracks, which matters when the two problems feed each other.

What is the typical duration of a partial hospitalization program?

The listed typical length is 7 days, though the actual schedule is set by clinical need and reviewed with your insurer. A partial hospitalization program is a daytime level of care, so you attend sessions Monday through Friday and sleep at home. Ask on the phone how extensions are handled if symptoms need more time.

What is the Intensive Outpatient Program on Long Island, and how does it differ from this one?

An intensive outpatient program is a step below partial hospitalization, usually fewer hours per week, and this center lists it among continuing care options. If your needs fall between weekly counseling and a full day program, then ask the clinical team which level fits, because insurers review the two differently and the answer changes what you pay.

Does Long Island have many treatment options besides this center?

SAMHSA FindTreatment.gov lists 83 facilities across Long Island as of the 2026 listing date, so this Port Jefferson program is one choice among many. If it is not the right fit, then a trained advisor on the free helpline can walk through other levels of care, check coverage and describe what each option involves, with no commitment required.

Seeing if this program suits you

Call the free helpline at any hour if you want to know more about the partial hospitalization program at Northwell Health Mather Hospital Port Jefferson or compare it with other Long Island options. A trained advisor answers, keeps the conversation private and charges nothing; what comes next is your call. Should you be calling for someone else have their insurance card nearby, since coverage for a hospital-based program is verified by phone before admission. When someone is drinking heavily or using benzodiazepines and withdrawal is a concern, then medical staff should supervise that period, and the helpline can point you toward medically appropriate care rather than guesswork.

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