Ghana has had relatively high immunisation coverage of more than 85% for infant antigens in the first year of life. However, there is a decline in immunisation coverage for vaccines provided during the second year of life (2YL) of the child. As part of the 2YL project implemented in Ghana to strengthen the 2YL immunisation platform, social mobilization strategies were utilised to help improve coverage for vaccines provided in the 2YL of a child. The study evaluated the impact of social mobilization components of the 2YL project on immunisation coverage in Adaklu district, Volta region, Ghana. A single-group pretest-posttest design was utilised to assess whether there was a significant change in immunisation coverage pre-and post-intervention. Data on health facilities’ immunisation coverage were collected from DHMIS II (District Health Management Information System) before, during, and after the intervention. The Pearson chi-square, fisher's exact, Wilcoxon sign rank test, and paired t-test were used to evaluate the impact of the intervention implemented in 2017 on identified outcomes mainly Penta3, MR1, MR2, and MenA. The results indicated a significant improvement in the dropout rate between the first and second dose of Measles-Rubella vaccines in health facilities within the district. The number of health facilities that recorded a negative dropout rate increased to 70% in 2018 from 25% in 2016. Also, the annual district immunisation coverage for the Second dose of Measles (MR2) increased from 73% in 2016 to 84% in 2017 and 82.5% in 2018. In addition, Penta 3 coverage increased from 90.6% in 2016 to 100 plus % in 2017. The implementation of the social mobilization had a positive effect on immunisation coverage in the district. The intervention resulted in increased immunisation coverage and significantly reduced the measles Rubella dropout rate.