Hallmark was established by Aralola Faturoti in the outskirts of Ondo town in 1995. Curriculum is Nigerian but some attention is paid to TOEFL and SAT. Far more hours is invested in Mathematics and English language subjects. The school is located in Italurowo Ondo-Akure Road, Ile-Oluji Junction, Ondo.
Hallmark Secondary School has an impressive open Basketball pitch. Library contains carefully selected books and there are boarding facilities. The school has been a recipient of some national awards. A student of the school, Titilayo Adewale was recognized for her achievements in a nationwide competition in Mathematics in 2013, a ceremony that was presided over by the Nigerian first lady, Dame Patience Jonathan.