Step-child inheritance tax calculator (Ireland 2026)

Step-children in Ireland are treated as Group A for CAT purposes, the same as natural and adopted children. The 2026 threshold is €400,000. This calculator works out the CAT on the excess at 33%, with prior Group A gifts aggregated.

Step-children in Ireland are treated identically to biological children for CAT purposes. They fall under Group A with the 2026 threshold of €400,000. This generous treatment reflects the intention of the Capital Acquisitions Tax Consolidation Act 2003 that blended families should not face a CAT disadvantage compared to traditional family structures.

Important: the step-parent relationship must exist at the date of the gift or inheritance. If the step-parent's marriage to the natural parent ended before the death, the step-child status ends too, and Group B or C applies instead.

How this calculator works

The calculator applies the 2026 Group A threshold of €400,000 to the step-child's inheritance. Prior Group A gifts and inheritances since 5 December 1991, including from both the step-parent and any biological parent who made Group A gifts, are aggregated under CATCA 2003 Schedule 2.

What to do with the number

If the inheritance is within the Group A threshold and there are no prior gifts, no CAT is owed. If the inheritance includes the family home and the step-child lived there for three or more years before the death, Dwelling House Exemption may apply, eliminating CAT on the home. The Complete Bundle includes the DHE check, the per-beneficiary calculation, and IT38 draft returns.

This calculator is a preparation tool using Irish tax rates and rules for 2026. It is not legal or tax advice. For complex estates, consult a solicitor or tax adviser. All values are estimates based on the information you provide.