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Mark O. Costley

About me

With more than 20 years experience in private practice, Mark Costley has helped hundreds of North Carolinians with estate planning, trust and estate administration, planning for children and adults with special needs, business succession planning and business transactions, and family charitable and philanthropic counseling. Mark’s work involves elements of teaching, strategic analysis and planning, negotiation, documentation, and assisting clients in executing their plans. A Duke University Alumnus, Mark has given back to his alma mater in numerous capacities, including serving as a member of the Board of Trustees. He has devoted his considerable energies to the Servant Center, Inc., a nonprofit corporation providing health care services for veterans and the homeless. Mark frequently provides public presentations on the subjects of estate planning, financial planning, asset protection, health care planning, retirement planning, and related topics. Mark is also a certified court mediator.


Mark is an active member of a variety of associations and committees, including the North Carolina State Bar, North Carolina Bar Association, Oklahoma Bar Association, American Bar Association, 14th Judicial District Bar, North Carolina Bar Association, Estate & Trust Legislative Committee, Durham-Orange Estate Planning Council, American Academy of Estate Planning Attorneys, and the National Academy of Elder Law Attorneys.


Mark is married to Margaret Costley, and has two daughters, Eleanor born in 1995, and Audrey born in 2000. He is an active member of University Presbyterian Church, in Chapel Hill, North Carolina, an avid sports fan, and enjoys reading, travel, tennis, music, politics and gardening.


Guiding Those Left Behind in North Carolina


Photos and videos

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Practice areas


  1. Estate Planning: 40%
  2. Elder Law: 25%
  3. Trusts: 15%
  4. Business: 10%
  5. Probate: 10%



Hourly ($310/hour), Fixed (sometimes)

Payment types:

Cash, Check, Credit card

Attorney endorsements

2 total 

Are you an attorney? Endorse this lawyer

  • Michelle P. Biddinger

    I endorse this lawyer. They are an expert in the field of estate planning.


    Michelle Biddinger Elder law Attorney
    Relationship: Fellow lawyer in community

  • Rupinder Singh Gill

    I strongly endorse this lawyer. Mark is an outstanding attorney.


    Rupinder Gill Estate planning Attorney
    Relationship: Co-worker

Contact info

Walker Lambe Rhudy Costley & Gill, PLLC

Palladian Corporate Center
240 Leigh Farm Road, Suite 100
Durham, NC, 27707

Walker Lambe Rhudy Costley & Gill, PLLC

102 Market Street
Suite 105
Chapel Hill, NC, 27516

Walker Lambe Rhudy Costley & Gill, PLLC

12450 Cleveland Road
Suite 203
Garner, NC, 27529



OKAuthorized to practice law198505/07/2010
We have not found any instances of professional misconduct for this lawyer.
Avvo contributions
Legal answers
Award nameGrantorDate granted
AV RatedMartindale-Hubbell2013
Leader in the LawNorth Carolina Lawyers Weekly2013
AV RatedMartindale-Hubbell2012
AV RatedMartindale-Hubbell2011
AV RatedMartindale-Hubbell2010
AV RatedMartindale-Hubbell2009
AV RatedMartindale-Hubbell2008
AV RatingMartindale-Hubbell1990
Work experience
TitleCompany nameDuration
PartnerAdams& Costley, PLLC1994 - 2000
PrincipalLaw Office of Mark O. Costley1991 - 1994
AssociateCrowe & Dunlevy1985 - 1990
Association namePosition nameDuration
National Academy of Elder Law Attorneys (North Carolina chapter)Member2010 - Present
National Academy of Elder Law AttorneysMember2009 - Present
North Carolina Bar Association, Estate Planning and Fiduciary Law Section, Legislative CommitteeN/A2005 - Present
North Carolina Bar Association, Elder Law SectionN/A2003 - Present
Durham County Bar AssociationN/A2002 - Present
Durham Orange Estate Planning CouncilPresident2001 - Present
American Academy of Estate Planning AttorneysN/A2000 - Present
American Bar Association, Real Property, Trust and Estate Law SectionN/A2000 - Present
North Carolina Bar Association, Estate Planning and Fiduciary Law SectionN/A2000 - Present
North Carolina Bar AssociationN/A1991 - Present
Oklahoma Bar AssociationN/A1985 - Present
American Bar AssociationN/A1985 - Present
Greensboro Bar AssociationN/A1991 - 2000
Oklahoma County Bar AssociationN/A1985 - 1990
American Bar Association, Litigation SectionN/A1985 - 1993
Publication nameTitleDate
BookGuiding Those Left Behind in North Carolina2006
School nameMajorDegreeGraduated
Duke University School of LawLawJD - Juris Doctor1985
Duke UniversityPublic PolicyA.B.1982
Speaking engagements
Conference nameTitleDate
Triangle Caregiver's ConferenceUnderstanding the Law Related to People Giving Care2013
Blue Cross Blue Shield of North Carolina EmployeesLegal Issues & Documents When Someone Decides for Someone Else2013
Duke UniversityPlanning with Trusts for IRAs2006
Trust DraftingDrafting Special Needs Trusts2003
Ethical Issues in North Carolina Estate PlanningEffective Client Communications2002
Choice of Business Entity in North CarolinaGeneral Partnerships and Joint Ventures2000
Judgement Enforcement in North CarolinaEnforcement of Judgments1998
Covenants Not to Compete in North CarolinaCovenants Not to Compete in Employment Arena1998