Being in a creative field, much of an interior designer's qualifications boil down to artistic ability. However, a handful of certifications add credibility to the title. The National Council for Interior Design Qualification, a nonprofit organization that establishes standards for design professionals, serves as the most prominent credentialing body, but it is not the only option for creative professionals looking to prove their qualifications.

NCIDQ Basics

Established in 1974, the NCIDQ's professional interior designer certificates recognize the qualifications and safe practices of designers, based on their ability to create safe, aesthetically pleasing and functional spaces. The NCIDQ assesses this ability by administering an examination; upon passing the examination, designers are issued a certificate and an NCIDQ certificate number, which they may present to employers and state regulators alike.

NCIDQ Eligibility

To take the NCIDQ's certification exam, you must first meet the organization's eligibility requirements. You can meet these requirements with a combination of educational and work experience qualifications, which vary greatly per individual. Typically, a B.A. or B.S. degree in a field such as architecture or design coupled with about 3,000 hours worth of qualified interior design experience makes you eligible for the test, though an associate degree coupled with about 7,000 hours of experience also works. The NCIDQ maintains a current list of eligibility requirements at their website.

NCIDQ Exam

To take the NCIDQ exam, you must first apply online at the organization's website. Once your application is processed, you'll have to pay a fee -- ranging from about $50 to $400 as of 2013 -- to take the test on-site. About 35 Prometric test centers across the country host NCIDQ exams, which you'll have to schedule online. The NCIDQ exam tests minimum entry-level competency for interior design with a combination of multiple choice questions and practice design problems.

Other Certification

As of 2012, approximately 300 post-secondary colleges and universities offer art and design degrees -- including interior design degrees -- accredited by the National Association of Schools of Art and Design, while about 150 schools offer bachelor's or master's degrees in interior design with programs accredited by the Council for Interior Design Accreditation. Likewise, the National Kitchen and Bath Association accredits 46 certificate, associate and bachelor's degree programs for kitchen and bath design. Most states require NCIDQ certification for professional interior design licensure -- in fact, some states require the certification before you can legally call yourself an “interior designer” -- but California requires a different exam via the California Council of Interior Design Certification.