Cosmas Onyia

Attorney Cosmas Onyia is a seasoned legal professional focusing exclusively on family law. With nearly two decades of experience, he has helped individuals navigate complex legal matters such as divorce, child custody, support, legal separation, and property division. His strong courtroom presence and negotiation skills make him a trusted advocate in sensitive family disputes.

Cosmas earned his Juris Doctor degree from the University Of Idaho Law School in 1991. Shortly after, he was admitted to the Washington State Bar in 1993 and the State Bar of Arizona in 1994. That same year, he was also admitted to practice before the United States District Court, District of Arizona—establishing his foundation for a focused legal career in family law.

Throughout his legal career, Cosmas has prioritized client understanding and strategic planning. Whether the issue is a high-conflict custody battle or a peaceful separation, he listens closely to his clients’ goals and creates tailored legal solutions. His thorough approach aims to protect rights while minimizing unnecessary stress and delays.

Known for his direct yet compassionate style, Cosmas treats each case with care and confidentiality. His practice covers everything from spousal support and paternity cases to grandparents’ rights and annulments. He remains focused on achieving practical, results-driven outcomes that enable clients to move forward with clarity and peace of mind.

Clients trust Cosmas because he communicates clearly, explains all available legal options, and works to find the most effective path toward resolution. He handles both courtroom litigation and alternative dispute resolution with equal confidence. His long-standing presence in the Phoenix legal community speaks to his commitment and reliability.

Cosmas Onyia’s reputation is built on professionalism, empathy, and proven results. He continues to guide Arizona families through their most challenging legal transitions with integrity and strength.

Law Office Affiliations

• Founder, Law Office of Cosmas Onyia
• Member, Washington State Bar
• Member, State Bar of Arizona

Licensed State

• Arizona
• Washington

Education

• University Of Idaho Law School
  Juris Doctor (JD)

Awards & Badges