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Theresa Kellington is a native of Bismarck. She graduated from San Diego State University in 1989 with a degree in Criminal Justice Administration. She then continued her education with the University of the Pacific – McGeorge School of Law, where she graduated with honors in 1992, passing the California State Bar exam the first time.

After her graduation, she joined a law firm in California, where she opened a civil litigation department and worked with them for 3 years. Theresa moved back to Bismarck after giving birth to her daughter in 1995 in order to be closer to her family. She began working with Pearce Durick and American Legal Services. 

Theresa joined Dan Oster in 2012, and they established Kellington & Oster, PC together. She loves family law, business planning, and estate planning cases. She is licensed to practice law in California and North Dakota and is also certified by the North Dakota Tribal Courts. Theresa has a 90% success rate.

She states, “Working with family law can be stressful, but I love to feel like I’m doing something right.” 

As a pro bono attorney of the year in North Dakota, Theresa aspires to become a Judge in the future. 

Call us if you want to hire Theresa Kellington for your legal issues.