Question 1

How to calculate the number of tax shares?

Accepted Answer

Tax shares are calculated as follows: married couple/civil partners = 2 base shares, single = 1 share. For dependent children: +0.5 share for the 1st child, +0.5 share for the 2nd child, +1 share for the 3rd child and each subsequent one. A single parent gets an additional half share. Children in shared custody count for half a share less. Examples: couple with 2 children = 3 shares, couple with 3 children = 4 shares, single parent with 1 child = 2 shares.

Question 2

Is the family quotient capped?

Accepted Answer

Yes, the tax benefit from the family quotient is capped. In 2026, the cap is €1,759 per additional half-share beyond the first two shares (for couples) or the first share (for singles). This cap limits the tax savings from dependent children for high-income households. Specific caps apply for single parents (€4,149 for the first additional half-share) and taxpayers who have raised one or more children alone.

Question 3

Until what age can an adult child be attached to the household?

Accepted Answer

An adult child can be attached to their parents' tax household until age 21 (unconditionally) or until age 25 if pursuing studies. The attached adult child does not need to file a separate return. Alternatively, parents can choose to deduct alimony paid to a non-attached adult child (capped at €6,674 per year in 2026). The choice between attachment and alimony depends on each household's tax situation and should be optimized each year.

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