William Michael Sullivan

William Michael Sullivan

4.9
Rating: 10.0

Licensed for 33 years

Family Lawyer at SAYVILLE, NY
Practice Areas: Family, Divorce & Separation, Marriage & Prenuptials

173 NORTH MAIN STREET - SUITE 317, SAYVILLE, NY

About William

Biography

Practice Areas

3

Practice Areas

Fees and Rates

Cost

Hourly Rates

$ 200-495 per hour

Retainer

Always


Payment Methods

  • Cash
  • Check
  • Credit Card

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Licenses

Licensed in New York for 33 years

State: New York

Acquired: 1992

Delinquent

No misconduct found

Location

The Law Office of William M. Sullivan

173 NORTH MAIN STREET - SUITE 317, SAYVILLE, NY, 11782

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William Michael Sullivan's Reviews

Avvo Review Score

4.9 /5.0

33 Client Reviews

Filter Avvo Reviews (33) Refine reviews to match your needs. Use the filters to quickly surface reviews that align with your case or priorities.

Showing 1 - 5 of 23 reviews | Advocacy

Posted by Ann | November 09, 2020 | Divorce & Separation

EXCELLENT!

Will came highly recommended by an attorney friend of mine. I consulted with Will for a separation agreement. He was patient, empathic, and provided excellent advice without any pressure. It was obvious during our conversations that he loves his work and is truly interested in helping people. I am... planning to hire Will to handle my case, he has extensive experience, he is tenacious when advocating for his clients, and understands the importance of building relationships. I know I will be in capable hands!

Posted by Jim | October 16, 2019 | Hired Attorney | Divorce & Separation

A Lasting Relationship

I was introduced to William Sullivan, aka “Will”, about 10 years ago by a mutual friend. I was in the early stages of divorce and needed some legal advice; my friend recommend I speak to Will. At the initial consultation I discussed with Will all my questions and concerns on the typical divorce to...pics of house, kids, assets and the like. He listened intently and provided his guidance and opinion on each topic and he quickly defined a plan of action for me. His knowledge of and experience in both Family and Finance Law along with his caring demeanor and hearty laugh immediately put me at ease. I hired him on the spot. In both the negotiation and court phase of my divorce, Will was my champion. He fought for me where it made sense and advised me when it didn’t. When the dust settled, I had a fair deal and most importantly an extensive parenting time schedule. Through the years since the divorce, I’ve kept in contact with Will. He has always been there to answer questions and provide guidance on all things Family Law related. Bottom line – he builds lasting relationships with his clients. In my opinion, not only is he an awesome attorney, but he’s also a great guy and someone I call friend.

Posted by Brian | March 21, 2019 | Hired Attorney | Divorce & Separation

A father's best friend!

A close friend of mine who is also a Divorce attorney recommended Will to me and I am very glad that he did. Will helped to guide me thru a very trying and challenging time in my life. My ex-wife decided to move almost 30 miles away and to uproot our children from their childhood home, schools and ...neighborhood. She even refused to sell the home back to me. Will provided me with excellent advice throughout this entire ordeal and in the end due to his tireless efforts and exceptional performance in the courtroom we were victorious and I was able to keep the children in their home and retain residential custody. A huge win for a father!

Posted by Pat | November 29, 2018 | Hired Attorney | Child Custody

Excellent Five Stars

William Sullivan is an excellent attorney. He is more than just an attorney, he is an expert in his field. He represented my husband and me in a grandparent custody/visitation issue. Will worked tirelessly, never leaving a stone unturned. He was on top of everything, prior to it even happening. ... His calls and emails are returned within a very timely window. Will's knowledge in cases like ours is astounding. He aligns himself 100 percent. The professionalism in the courtroom is there. The comfort zone is there. The reliability is there. The assurances are there. Do not hesitate in contacting him.

Posted by Matthew | September 24, 2018 | Hired Attorney | Family

Best of the Best

Will has been a true savior, guiding me like a true professional and friend during this difficult time. Even when emotions can distract you from the right course of action, Will was there to listen and help me do what was right for my daughter. He has been by myside during all the proceedings and alw...ays available at any time to back me up. He is a true safety blanket that is always one step ahead. He is aggressive and tactful backed up with professionalism and efficiency. Many times he has put my fears to rest after being faced with difficult decisions in this tough tribulation. Will was always been truthful and out for my best interests, clearly exsplaining everything to me and getting the exact results he said he would. Without a doubt, I would want no one else but him in my corner during tough times.

See All Client Reviews

William Michael Sullivan's Lawyer Endorsements

Endorse William
Somair Syed Alam headshot
Somair Alam

Family lawyer | Feb 13

Relationship: Fellow lawyer in community

"Very knowledgeable family law attorney, dedicated to his clients' success."

Catherine E. Miller headshot
Catherine Miller

Divorce and separation lawyer | Sep 24

Relationship: Fellow lawyer in community

"Ms. Sullivan is highly respected by his colleagues for his professional conduct, intelligence and tenacious representation of his client."

Karen Svendsen headshot
Karen Svendsen

Divorce and separation lawyer | May 15

Relationship: Co-worker

"I endorse this lawyer. Mr. Sullivan is an extremely tough and competent litigator who stops at nothing to pursue the rights of his clients. In addition, Mr. Sullivan has integrity and always treats his clients with the utmost respect and personal attention. I highly recommend this attorney for any Family Law matter."

Ettore A. Simeone headshot
Ettore Simeone

Divorce and separation lawyer | May 12

Relationship: Fellow lawyer in community

"I endorse this lawyer. Will is truly on of the finest attorneys I have ever met in my 32 years of legal practice. He is a wealth of knowledge about any aspect of Family Law and i often call him when I have a complex legal question to get his learned opinion, which I highly respect. He is always willing to assist a colleague. He is highly ethical and competent. I respect him greatly and give him my highest endorsement."

View All Endorsements
Brittany A. Fiorenza Esq. headshot
Brittany Fiorenza

Divorce and separation lawyer

Experience

Rating:  10.0 (Superb)

Honors

2014

Top Attorneys in Long Island, Legal Leaders

1992

Trial Advocacy, Villanova University School of Law

1991

Moot Court Board, Villanova University School of Law

Work Experience

2003 - Present

Partner, Long Tuminello, LLP

2001 - 2003

Managing Partner, William M. Sullivan, P.C.

1992 - 2001

General Counsel/Director of Compliance, AMBAC Financial Services, Inc.

Associations

2014 - 2015

Suffolk County Matrimonial Bar Association

President

2013 - 2014

Suffolk County Matrimonial Bar Association

Vice President

Sample of Legal Cases

O'Loughlin v. Sweetland App Div 2nd Dept. 2009-02720

Appellate Division Reversed

See More Legal Cases

Education

1992

Villanova

JD - Juris Doctor

1987

University of Notre Dame

BBA - Bachelor of Business Administration

Speaking Engagements

2014

Hot Button Topics in Matrimonial and Family Law - November 7, 2014 Hague Convention and Other International Treaties and laws and effects on counseling clients

2010

Matrimonial Boot Camp

Financial Disclosure

Publications

2014

Legal Leaders Legal Leaders: Long Island Top Rated Lawyers

Languages

English

Activity

Avvo Rating

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Avvo Rating Levels
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