Child maintenance calculator in Ireland: what the State tool does and does not do

For years the most common question from separating parents in Ireland, "how much child maintenance should be paid?", had no official answer. There was no table, no percentage and no State tool. That changed when the Department of Justice, Home Affairs and Migration launched an online child maintenance calculator at childmaintenancecalculator.ie (the Department dates the launch to January 2026). This guide explains what the calculator is, what it asks for, what its number means and does not mean, and how to use it when you negotiate or go to court.

What the calculator is

The child maintenance calculator is a free website run by the Department of Justice, Home Affairs and Migration. You enter details about both parents and the children and it produces an estimate of an appropriate level of child maintenance.

The Department is careful about what that estimate is. In its own words:

"You can use this calculator as a starting point for discussions on child maintenance."

and

"The estimate provided by the child maintenance calculator is not legally binding or enforceable, nor will it change an existing court order. It is a guide only."

It also warns that you "should not rely on its estimate as a guarantee of future income or payment". If you cannot agree after using it, the site points you to the Legal Aid Board's free Family Mediation Service.

The site says it does not save or track anything you enter and that a session expires after 60 minutes of inactivity, so have your figures ready before you start.

What it asks for

Because the result turns on both incomes, it is only as reliable as the figures both of you put in. Where one parent is self-employed or has irregular income, agree what period you are averaging before you compare results.

What the number means

The estimate is a benchmark, not an entitlement. It is useful because it gives two parents who disagree a neutral starting figure that neither of them invented. It does not:

• bind either parent;
• bind a judge;
• change, suspend or replace a maintenance order already made by a court;
• take account of exceptional costs such as a child's disability, private school fees already being paid, or a parent's own disability.

A judge deciding child maintenance applies the law, not the calculator. The Courts Service says a judge considers each parent's income, assets, expenditure (including the costs of raising the children) and supports for other people. Those are broader than the calculator's four inputs, so expect the court figure to differ where your circumstances are unusual.

Who counts as a dependent child

Both parents must support their dependent children, whether or not they were married. The Courts Service defines a dependent child as one who is under 18, or over 18 and under 23 and in full-time education (or who would be if a maintenance order were made), or of any age with a mental or physical disability that means they cannot maintain themselves. Child maintenance under a court order ends automatically when the child stops being dependent.

Using the result in a negotiation

Most parents never go near a courtroom over maintenance. The calculator works best as a shared reference point:

1. Each of you runs it with the same inputs, so there is one number to talk about.
2. Add the costs the calculator cannot see: childcare, school costs, medical needs, travel for access.
3. Decide how to handle changes: an annual review date, a rule for what happens if either income changes by a set amount, and who pays one-off costs.
4. Write it down. An informal agreement is better than nothing, but it cannot be enforced by attachment of earnings. Many parents have the agreed terms made a court order by consent, which costs no court fee, or include them in a separation agreement.

If you cannot agree, the Family Mediation Service is free and a mediator can run the calculator with you. Mediation is voluntary and either of you can stop it.

Using the result in court

You can bring the calculator result to a maintenance hearing, and there is nothing to stop you telling the judge you ran it. Treat it as one piece of evidence of what a reasonable figure might be, not as the answer. The judge will want the underlying facts: payslips, bank statements, a list of the children's actual costs, and your own outgoings. In District Court maintenance cases the judge can order up to €150 per week per child; in the Circuit Court, where maintenance is dealt with as part of judicial separation or divorce, there is no cap and the court must make proper provision for the children under section 20 of the Family Law (Divorce) Act 1996.

How child maintenance is enforced

A maintenance order is enforced through the District Court. The Courts Service lists two main routes:

• Attachment of earnings order. The court directs the paying parent's employer, or private pension provider, to deduct maintenance from wages, salary or pension and pay it over. Under section 10 of the Family Law (Maintenance of Spouses and Children) Act 1976 the court fixes a normal deduction rate and a protected earnings rate below which pay cannot be cut. Since 1996 the court must consider making this order at the same time as the maintenance order itself.
• Application to recover arrears. You file an application and the court office issues a summons requiring the other parent to attend a hearing. The judge can adjourn to let arrears be paid, vary the order, or treat the failure as contempt of court, which can include an order to imprison the debtor.

Where the other parent lives abroad, the Central Authority for Maintenance Recovery in the Department of Justice can help you enforce an Irish order in another country.

What to do if the other parent will not pay

• No agreement yet: run the calculator, propose a figure in writing, and offer mediation. If that fails, apply to the District Court for a maintenance order; there is no court fee for family law applications.
• Informal agreement being ignored: you cannot enforce it as it stands. Apply for a maintenance order, using the calculator and your records of what was agreed as evidence.
• Court order being ignored: apply for attachment of earnings if the other parent is employed or drawing a private pension, or apply to recover arrears if not.
• Other parent's income has fallen: they can apply to vary the order. Until a court does so, the existing amount is due, and arrears keep building.

Tax

Revenue says maintenance payments for the benefit of children are ignored for Income Tax. The payer gets no deduction and the receiving parent pays no Income Tax, USC or PRSI on them. Keep child maintenance separate from any spousal maintenance in your agreement or order, because spousal maintenance that is legally enforceable is taxed differently.

Where this leaves you

The State calculator gives you something Irish parents did not have before: a neutral starting figure. It will not settle an argument on its own and it will not move a court. Use the maintenance and pensions tool to walk through what the calculator result means alongside your other outgoings, and to check whether either parent's pension needs looking at. If you are married and heading for separation or divorce, the solicitor page explains how to find someone who can turn an agreed figure into an enforceable order.