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Mario Albert Sullivan

Landlord or tenant Attorney at Chicago, IL

4.5   8 reviews
  • Licensed for 18 years
    State IL
    Acquired 2005
    Active and Authorized to Practice Law No misconduct found

We have not found any instances of professional misconduct for this lawyer.

About Mario

Learn Mario’s areas of practice.

Practice areas
  1. Landlord or tenant
    Representing Landlord and Tenants

    19 years, 200 cases

  2. Real estate
    Representing Sellers and Purchasers

    19 years, 200 cases

  3. Contracts and agreements

    19 years, 100 cases

  4. Chapter 13 bankruptcy
    Creditors Rights

    19 years, 20 cases

  5. Corporate and incorporation

    19 years, 20 cases

  6. Debt collection

    19 years, 50 cases

  7. Estate planning

    19 years, 20 cases

  8. Litigation

    19 years, 200 cases

  9. Wills and living wills

    19 years, 100 cases

  10. Foreclosure
    Represent Banks and Receivers

    19 years, 10 cases

Mario is a named partner at Johnson & Sullivan, Ltd. in Chicago, Illinois.  He counsels clients on a wide range of issues relating to real estate, landlord/tenant, creditor bankruptcy, employment, contract law, business formation, and estate planning. 


Mario serves as 2014-2017 Nominating Committee Representative for the ABA Young Lawyers Division (YLD); a 2014-2015 YLD Liaison to ABA Judicial Division and American Bar Endowment; a 2014-2015 Council Member on the ABA Council on Racial and Ethnic Diversity in the Educational Pipeline Council; Co-Chair to the ABA Individual Rights & Responsibilities Bullyproof Committee; a Board Member and Co-Chair of the Program Committee for the LAGBAC; and a Board Member to the LGBT Bar. 


Mario is a former PILI Intern and member of the Public Interest Law Initiative (PILI) Alumni NetworkLeadership Council, and has previously served as: 2013-2014 YLD Chair, 2012-13 YLD Chair-Elect, 2011-2012 YLD Secretary-Treasurer, 2010-2011 YLD Conference, Program, and Products Director, 2009-2010 YLD Diversity Director, Committee member to the ABA YLD Diversity Team and Resolutions Team, and National Representative for the LGBT Bar to the YLD; Vice-president of LAGBAC; Planning Committee - Fundraising member for Equality Illinois 2005 Gala; Chair of the local host committee for the LGBT Bar’s Lavender Law – 2007; and Chair and vice-Chair of the CBA Committee on the Legal Rights of Lesbians and Gay Men.

Photos and videos


Johnson & Sullivan, Ltd.
11 E Hubbard St Ste 702
Chicago, IL, 60611-3536

Landlord & Tenant lawyers nearby


4.5 / 5.0
  8 customer reviews
5 Star
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1 Star
Posted by Tom | June 29, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Responsive, professional, and calm
I've used Mario to both sell and buy a home. He's experienced, responsive, and just gets the job done with as little hassle as possible. I highly recommend.
Posted by anonymous | June 12, 2017
This review is from a person who hired this attorney.
| Hired Attorney
My go to real estate attorney
Mario has been my go-to real estate attorney for 3 years. He and his team are organized, efficient, prompt responders, and have systems in place so nothing ever falls through the cracks. They deliver exceptional customer service and always go above and beyond to ensure a smooth transaction for their clients. I have personally completed more than 25 real estate transactions with him, and my clients have employed him for their other real estate law related issues.. By far the best real estate attorney I have worked with in 12 years.
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Posted by Carol | June 5, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Great Experience
When we bought our condo this year it had been 18 years since our last purchase. Enough had changed and Mario was great in walking us through the process step by step. He made the process simple, promptly answered all our questions and was very good with emailing us updates and keeping us on track with deadlines. Mario was great. He was always calm and competent and a pleasure to work with, which are great qualities. If we purchase another property we will definitely have Mario be our attorney again.
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Posted by Simon | May 12, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Professional & Responsive
Been working with Mario since 2001 and have had great results. On many occasions he was able to get my Real Estate firm out of binds, whether with tenants or contractors.
Posted by Brittany | May 10, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Top Notch Attorney
I have had Mario as my attorney for several properties within my company as a Property Manager. He has always been extremely knowledgeable and professional with every case I have brought him, no matter how many crazy questions I have for him. He always thinks about my property's best interests and gives insightful advice. He has successfully helped my properties on more occasions than I count. Not only is he a great attorney, but he is also a great person to work with for the several years I have known him. I would recommend him for a company or someone who needs real estate help and have sent many of my colleagues and friends to him. Top notch attorney Mario is!!
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Posted by Aaron | May 10, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Trusted and Keeps Me Calm
I started employing Mario in 2013 to help with repeated legal threats from owners in my small condo building. There are only 8 units in my building and we're self managed. The first threat came when 2 owners continued to veto having our back decks (built of wood in 1997) replaced or repaired so I told them I would have to report the issue to the city. The city did finally evaluate and the association received a citation and fine for safety violations, not the building code violations I reported. They threatened to sue me to pay for the association's attorney fees to address the citation, so I needed Mario to tell me my liability. The threats didn't stop there. They also threatened legal action to have the board rent out my parking space (a limited common element assigned to my unit) to pay for the deck replacement; again Mario was fantastic coaching me through it and keeping me calm. Since hiring Mario there were probably 10-12 threats between 2 owners directly at me ranging from the grill on my deck to a friend who brought their dog in my unit, all of which went nowhere and most had no basis. Over the years I have come to thoroughly trust Mario's counsel and ability to keep me calm through even the most ridiculous threats.
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Posted by Joel | May 10, 2017
This review is from a person who hired this attorney.
| Hired Attorney
Extremely responsive, professional, and knowledgeable
I am a physician, and was referred to Mario from another attorney to handle a collections case. Mario responded to both e-mail and phone very quickly, which assured me I was in good hands. He kept me informed of what was going on the entire time, and gave great advice/feedback on the negotiations. He got us great results in a very timely manner. I highly recommend his services, and will use him again in the future!
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Posted by William | May 3, 2017
This review is from a person who hired this attorney.
| Hired Attorney
I have been paying Mario Sullivan's legal practice for over a year to collect on a judgment against a fraudulent contractor that defrauded me of some money. Mr. Sullivan had one job, ONE JOB, to do, and that was to get the contractor served to get him in the courtroom. The process server he uses did not get the contractor served, yet Mr. Sullivan's office thinks it acceptable to bill the client for services that are not performed. He then continues billing for services that need to be performed such as showing up for court to attain a continuation because of his failure to perform with the process service. I would find an attorney that provides performance based billing so they will get the job done. Unfortunately, Mr. Sullivan bills for his "time," not performance, which leaves no motivation to get the job done on his clients' behalf. Terrible way to do business, and I am seriously considering filing a complaint with the bar association for the state of Illinois over this. My advice is to look elsewhere if you are in need of an attorney who will get you across the finish line, not just bill you for running the race.
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  • Free Consultation 10 minutes
  • Hourly Rates $ 245-295 per hour
  • Contingency 33%-60%
Payment methods
Cash, Check, Credit Card


AVVO RATING 10.0 (Superb)

Work Experience

  • Partner
  • Johnson & Sullivan, Ltd.
  • 2005 - Present


  • John Marshall Law School, Chicago
  • JD - Juris Doctor
  • 2005
  • Illinois State University
  • BS - Bachelor of Science
  • 2000


  • Lesbian and Gay Bar Association of Chicago
  • Board Member
  • 2005 - Present
  • National LGBT Bar Association
  • Ad-hoc Board Member
  • 2003 - Present
  • Illinois State Bar Association
  • 2002 - Present
  • American Bar Association
  • 2002 - Present
  • Chicago Bar Association
  • 2002 - Present
  • American Bar Association, Young Lawyers Division
  • YLD ABA Nominating Committee Representative
  • 2014 - 2016
  • American Bar Association, Young Lawyers Division
  • Chair
  • 2013 - 2014
View all associations

Languages Spoken

  • English

Honors and Awards

  • Star of the Year
  • American Bar Association, Young Lawyers Division
  • 2011
  • Star of the Year
  • American Bar Association, Young Lawyers Division
  • 2010
  • Star of the Quarter
  • American Bar Association, Young Lawyers Division
  • 2008
  • Certificate of Appreciation
  • Chicago Bar Association
  • 2007
View all awards

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Chicago Landlord or tenant Lawyer Mario Albert Sullivan
Mario Albert Sullivan
Landlord or tenant Attorney
Chicago, IL
Licensed for 18 years
Free Consultation