When the child reaches the age of eighteen (18) years, child support payments ends.
In Ghana, once the child reached the age of eighteen (18) years, the parent paying child support does not need to file a motion with the court to state the child has reached eighteen (18) years and  to seek permission to stop making the payments. It stops automatically.

The courts in some situations may extend child support payments if the child reaches the age of eighteen (18) years and has a mental and physical disability that must be taken care of and provided for by the parents or other circumstances that may arise.