Adolescents' early sexual debut contributes to their huge burden of sexual and reproductive ill-health, especially in sub-Saharan Africa. Reports continually reveal that female adolescents, in particular, constitute a large portion of the 34 million people living with HIV worldwide. Other consequences associated with early adolescent sexuality include unplanned pregnancies, unsafe abortions and sexually-transmitted infections. In light of this, the article analyses approaches adopted by Nigeria and South Africa in fulfilling their international law obligations to respect, protect and fulfil adolescent girls' right to access contraceptive information and services, specifically, in their domestic legislation, policy documents and court decisions. Sexuality education is compared, as well as actual access. There is extensive evidence of the measures put in place to ensure adolescent girls' access to contraceptive information and services in Nigeria and South Africa. Although the level and extent of the barriers faced by adolescent girls when accessing contraceptive services and information vary, the consequences are similar: We find that Nigerian and South African adolescent girls, generally, lack access to contraceptive information and services. Despite measures to ensure adolescent girls' access to contraceptive information and services in Nigeria and South Africa, several gaps remain.