Sergei B Thomas

Sergei B Thomas

4.1
Rating: 8.9

Licensed for 35 years

Child custody Lawyer at Denver, CO
Practice Areas: Child Custody, Divorce & Separation, Guardianship ... +2 more

1407 Larimer Street, Suite 206, Denver, CO

About Sergei

Practice Areas

5

Practice Areas

Child Custody 40%

Parenting time disputes in cases involving divorce, allocation of parental responsibilities, grandparent rights, motions to restrict parenting time, and psychological parent cases to resolve parenting schedules, child support, allocation of the tax dependency exemption, decision making and payment of unisured medical or extracurricular expenses. Often such cases involve use of experts appointed by the Court to investigate the issues in the case. to address parenting disputes.

19 years

40%
Divorce and Separation 40%

Dissolution of marriage, legal separation, with issues of marital assets (stocks, investment and retirement accounts, separate property that has increased in value during the marriage) and debt division,

19 years

40%
Guardianship 10%

For cases in which a sole parent has passed away, has been hospitalized or may incapacitated, or where parents may have substance abuse or mental health issues rendering them incapable of safely caring for the minor children in their custody, or where

19 years

10%
Adoption 5%

Stepparent, kinship,and second parent adoptions with the accompanying relinquishment proceedings.

19 years

5%
Marriage and Prenuptials 5%

Prenuptial agreements as well as postnuptial agreements whch are drafted in order to protect the interests of the parties in the event that a marriage is sought to be dissolved.

19 years

5%

Fees and Rates

Cost

Free Consultation

$0 first 30 minutes

Hourly Rates

$ 250-250 per hour

Retainer

Always


Payment Methods

  • Cash
  • Check
  • Credit Card

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Licenses

Licensed in Colorado for 35 years

State: Colorado

Acquired: 1990

Active

No misconduct found

Location

Thomas Law Group, P.C.

1407 Larimer Street, Suite 206, Denver, CO, 80202

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Sergei B Thomas's Reviews

Avvo Review Score

4.1 /5.0

13 Client Reviews

5 star (10)
4 star (0)
3 star (0)
2 star (0)
1 star (3)

Posted by Alison | April 24, 2025 | Hired Attorney

This review is from a person who hired this attorney.

Extremely Knowledgeable and Professional Attorney

Sergei was extremely knowledgeable and professional. I'm an HR professional based in WA state but also have employees in CO state and I needed an experienced attorney to help with an employee relations issue. Sergei and his staff made me feel comfortable right from the start. He explained the process... thoroughly and in a way that I could understand. I couldn't have resolved the case successfully without him.

Posted by Joe | February 25, 2025 | Consulted Attorney

This review is from a potential client who consulted with this attorney.

Stay Away! He lost his own divorce case!

This guy lost his own custody case to his ex wife Lydia Thomas. See below. https://caselaw.findlaw.com/court/col-crt-app-div-iii/2144897.html He is a lying coward and says horrible things about minors, yet lost his own son to his ex wife.

Posted by Sherri | October 10, 2021 | Hired Attorney

This review is from a person who hired this attorney.

The best lawyer

He told me exactly what was going to happen and he was by far the best lawyer for my custody case.. He is knowledgeable and knows what he is talking about. Other lawyers told me I would lose but I won thanks to him. Very honest lawyer. If you need a great lawyer he is him.

Posted by anonymous | July 17, 2019 | Hired Attorney

This review is from a person who hired this attorney.

Regret hiring Sergei

I hired Sergei because the initial consultation was smooth, and everything laid out was in line with my objectives. After I hired him, there were long periods where he was working other cases and came back to mine only when the deadline was coming due. He would then work late, last minute phone tag w...ith my ex and I without any kind of recording, and when we went to court, my ex had pretended like none of the conversations had happened. Additionally, while sitting in court he would have casework on his computer for another client...definitely not my case because the names in the documents were none of my kids, my ex, or me. During the breaks at court he would be on the phone with other clients, and not discussing what to expect while at court, what was coming, or what he was going to do for me on my case. As the months had dragged on in this process, his clerk would file paperwork with the court that had material errors that needed to be corrected (at my expense, again), and these documents would continue to drag out my case because the financial numbers were so inflated my ex would continue to refer back to them and I'd have to provide the same statements over and over again. When he would "bargain" with my ex, it always came to surrendering more and more of my assets in exchange for moving things along. Giving up 60%, then 65%, then 70% of my 401 in exchange for getting the divorce settled and over with. I eventually had to ask that he no longer represent me in my divorce because I couldn't afford his services. There was further dispute when the severance date was, and this was adjudicated in court as well when he placed a lien on any marital assets I may be awarded. In addition to the disputed bill, I was billed for the hourly rate of him and others at his firm to file suit against me, also being added to the lien. This debt, for several thousands more, is currently in collections and I'm looking at a chapter 7 to get clear of it. I'm glad some people were pleased with his services...but I regret hiring him with every collection call I receive.

Sergei Thomas

Replied last July 18, 2019

I have no issue with being accountable for my actions. However, this review is filled with statements which have not been a part of any case that I've handled. I have never had "late-night phone tags" with any opposing party. I don't take calls during court breaks. The only time there are "court breaks" is during a permanent orders hearing, and I have not had permanent orders hearing where I take calls from other clients during breaks. I have NEVER had any client barter away their retirement assets in order to settle a case. I have not filed suit against any client. The statements in this review appear to be manufactured by someone who was not my client.

Posted by Allison | March 20, 2019 | Hired Attorney

This review is from a person who hired this attorney.

Highly Recommended

I had a few lawyers before Sergei for the last four years on my son's custody case. The previous lawyer created so much mess in my son's custody case. Sergei took care of some of her mess very well. He guided me so well and force another party to offer an agreement with me. My friend referred me ...to Sergei. I am so glad I hired him. He handles the case and communication very professionally and timely in the best interest of the client. Sergei, my personal thank you. Thank you for what you doing for me and my son. Allison

See All Client Reviews

Sergei B Thomas's Lawyer Endorsements

Endorse Sergei
Maha Kamal headshot
Maha Kamal

Family lawyer | Jan 18

Relationship: Worked together on matter

"I endorse this lawyer. I had the pleasure of working with Mr. Thomas at our previous law firm. He's incredibly knowledgeable of the law and also incredibly experienced. He's also very thoughtful, putting his clients' needs and goals first. I wouldn't hesitate recommending him to anyone. We're lucky to have him as part of our Bar."

Ronald G. Walls II headshot
Ronald Walls

Family lawyer | Jan 18

Relationship: Fellow lawyer in community

"I have had the privilege of working with Mr. Thomas. He is well versed in all aspects of the law. What is truly striking about Mr. Thomas is his empathy for his clients. He will certainly present clients with well researched options and case strategies, however, he will always keep their best interests at heart. I highly recommend him for any family law matter."

Autumn Charlie Scardina headshot
Autumn Scardina

Child custody lawyer | Oct 14

Relationship: Opposing Counsel on matter

"I endorse this lawyer."

Zachary Alexander Chapman headshot
Zachary Chapman

Child custody lawyer | Mar 17

Relationship: Co-worker

"Mr. Thomas is a widely respected attorney both in his current office and throughout the Denver Metro Area. His knowledge of all aspects relating to Domestic Relations and Juvenile law is phenomenal and his ability to strategically plan and execute has awarded him with many favorable outcomes and satisfied clients."

Rachel L. Young headshot
Rachel Young

Unknown lawyer | Mar 17

Relationship: Co-worker

"Sergei is a dedicated and diligent attorney. He zealously represents his client while maintaining high standards of compassion and professionalism. I recommend Sergei as a family law attorney."

Jason A. Marquez headshot
Jason Marquez

Divorce and separation lawyer | Mar 14

Relationship: Supervised lawyer

"I endorse this lawyer."

Robert Samuel Willett headshot
Robert Willett

Criminal defense lawyer | Mar 04

Relationship: Fellow lawyer in community

"I endorse this lawyer. I have know Serge for 20 years, He was a Deputy DA when I was a cop. I am now an attorney. Serge is skilled, dedicated, hard-working, and possesses sterling integrity. I highly endorse him in all areas of practice."

John Paul Prentiss headshot
John Prentiss

Family lawyer | Mar 04

Relationship: Co-worker

"I endorse this lawyer. Sergei is knowledgeable, experienced, and great to work with. You couldn't ask for a better attorney."

Christopher Robert Basler headshot
Christopher Basler

Family lawyer | Jan 14

Relationship: Co-worker

"I endorse this lawyer. Mr. Thomas is a kind hearted and empathetic attorney that works diligently for the best interests of his clients and their children. Mr. Thomas is a highly skilled litigator and well respected in the community."

View All Endorsements
Chris Halsor headshot
Chris Halsor

DUI and DWI lawyer

Maha Kamal headshot
Maha Kamal

Family lawyer

Ronald G. Walls II headshot
Ronald Walls

Family lawyer

Zachary Alexander Chapman headshot
Zachary Chapman

Family lawyer

Rachel L. Young headshot
Rachel Young

Family lawyer

John Paul Prentiss headshot
John Prentiss

Family lawyer

Jason A. Marquez headshot
Jason Marquez

Family lawyer

Russell Stuart Ray headshot
Russell Ray

Criminal defense lawyer

Rachel Anne Markel Catt headshot
Rachel Catt

Family lawyer

Experience

Rating:  8.9 (Excellent)

Honors

2016

Distinguished, Martindale-Hubbell

Work Experience

2016 - Present

Owner, Thomas Law Group, P.C.

2014 - Present

Senior Associate, Johnson Marquez Legal Group

2006 - 2014

Associate, Matthews & Matthews, P.C.

1990 - 2006

Deputy District Attorney, Jefferson County District Attorney's Office

1989 - 1990

Law Clinic Participant, Washburn University School Of Law

1988 - 1990

Legal Internal, 1st Judicial District of Jefferson County

Associations

2015 - Present

Sam Cary Bar Association

Member

2006 - Present

Adams County Bar Association

Member

2006 - Present

Colorado Bar Association

Member

1999 - 2006

Colorado Appointed Special Advocates

Board of Directors

1999 - 2006

Jefferson County Juvenile Review Board

Board Member

Education

1990

Washburn University School of Law

JD - Juris Doctor

1986

University of Colorado - Boulder

Bachelor of Arts

Languages

English

Spanish

Activity

Avvo Rating

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Avvo Rating Levels
10.0 - 9.0 Superb8.9 - 8.0 Excellent7.9 - 7.0 Very Good6.9 - 6.0 Good5.9 - 5.0 Average4.9 - 4.0 Concern3.9 - 3.0 Caution2.9 - 2.0 Strong Caution1.9 - 1.0 Extreme Caution