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Child support calculator for a child — estimated amountTable of contents
An increase in child support is possible when there is a material change in circumstances (Art. 138 KRO). The change must be real and lasting, not temporary.
If you are filing for support for the first time, see: Child support petition: how to file step by step. If you need a reduction, see: Reduction or termination of child support.
Child support covers the maintenance and development of the child. The duty arises when the child cannot support themselves or their needs are not met by the other parent.
Typical situations include:
The key is proving that the change is significant and affects needs or capacity.
In the claim, specify:
A simple “before and after” cost comparison helps demonstrate the scale of change.
Useful documents often include:
The court looks at two main groups of factors.
Real and justified costs: housing, food, education, health, transport, activities. Costs must be reasonable and documented.
Not only current income, but earning potential, qualifications and assets. Irregular income can also be considered.
The court considers the other parent’s care contribution, other support obligations and the real division of costs.
Courts focus on durable changes. One‑off expenses or short‑term income drops are usually not enough. If costs are temporary, it is better to document them clearly and explain why they should still influence the amount.
When the other parent works irregularly or has business income, courts can look at lifestyle indicators, assets and earning potential. Provide any credible information that shows real capacity rather than only declared income.
Start from the updated monthly cost breakdown, subtract the child’s own income or benefits, and then compare each parent’s share based on capacity and care. This makes the request transparent and defensible. Even a simple table can be persuasive if it is consistent.
Usually from the date the claim is filed, unless the court sets another date. Do not delay if costs have materially increased.
For detailed criteria, see: Child support amounts: criteria and rules.
Typical reasons include:
The obliged parent can argue, for example:
If both sides can agree on an updated cost breakdown, mediation may lead to a settlement approved by the court. This often saves time and reduces conflict.
If possible, attach a short narrative that links the increase to concrete events (e.g., new school fees or medical treatment). This helps the court see why the change is material. Clear dates and amounts make the change easier to verify. Attach the most recent documents first. Consistency matters. Keep the narrative readable.
You can use the child support calculator as a reference point, but it is not binding and should be compared with real costs and evidence.
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