• Knowledge of contraceptives is high among migrant adolescent girls but usage is low. • High fertility among migrant adolescent girls is established. • There is an unmet need for family planning among migrant adolescent girls. • SES and other socio-demographic variables explain contraceptive use. • The study provides a chance for SRH education and promotion among migrant adolescent girls. This article examines the knowledge levels and experiences of contraceptive use among migrant, adolescent girl, head porters in Ghana, with the aim of igniting interest among relevant stakeholders for sexual and reproductive health education and promotion among migrant adolescent girls in Ghana. Through a quantitative cross-sectional research design, time-location and centres of aggregation sampling techniques were used to draw the study sample of 503 adolescents for a survey in the cities of Accra and Kumasi. Closed ended questionnaire were used to collect data. STATA version 14.0 software was used to analyse the data. Specifically, cross tabulation, chi-square test of association, and the Cramer’s V correlation coefficient and logistic regression techniques were used to evaluate relationships between selected variables. The findings illustrated high knowledge or awareness levels of contraceptives but low usage—78% of migrant adolescent girls had knowledge of contraceptives but only 13% used them. Only 14% of those who had had sexual intercourse, used a condom on each occasion of sexual encounter. Age, education, socio-economic status (SES) and ethnicity significantly predicted contraceptive use. Older adolescents 15–19 years (OR = 3.52, p < 0.05, CI = [0.02–0.82], those who attained Secondary/Technical (OR = 4.39p < 0.05, CI = [0.40–4.80], those who were not poor (OR = 4.60p < 0.05, CI = [1.49–14.19], and ethnicity (Gonjas) (OR = 4.35p < 0.05, CI = [1.33–14.21], significantly predicted the use of contraceptives among the adolescent girls. We recommend that the Ministries of Gender, Children and Social Protection and Education, must collaborate to enroll and retain migrant adolescent girls in Ghana’s Free Senior High School System. Additionally, the Ministries of Health and Gender, Children and Social Protection, must collaborate to establish safe and friendly adolescent youth centres in Ghana’s urban cities, specifically for migrant adolescent girls, to address their sexual and reproductive healthcare needs.