It is important to note that with regards to child maintenance, a child is seen as someone under the age of 16 or under the age of 19 in full-time education (not higher than A-level).
Sometimes, an application will be made by the primary carer of the children to the Child Support Agency, soon to be replaced by the Child Maintenance Service, although it is worth noting that they are unable to make an assessment if the other parent is living abroad. Going via these two agencies will mean that you get the most basic level of child support available to you as the primary carer.
Whether you use the Child Support Agency or the Child Maintenance service will depend on a number of things including how many children you have. The Child Support Agency calculates support through the other parent’s net income whereas the Child Maintenance Service calculates using the other parent’s gross income. It is worth noting that both of these bodies have the power to take payments directly out of income.
If the non-resident parent is a high earner (more than £104,000 per year) then the Child Support Agency has a limited role. The court can then order what to do with regards to child maintenance.