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Form 100. 2018 Personal Income Tax return

10,8,12. By large family

A deduction of 500 euros is established for large families. The concept of large families for these purposes is that established in Act 40/2003, of 18 November on Protection of Large Families (BOE 19/11/2003).

However, the deduction will be 1000 euros when any of the spouses or descendants to whom the "tax-free threshold for descendants" is calculated have a degree of disability of 65% or more. 100 Similarly, a degree of disability of 65 per cent or more will be considered accredited in the case of taxpayers whose disability is legally declared, even if this degree is not reached. 100

The deduction will be increased by 820 euros for each descendant, starting from the fourth inclusive, to which the "tax-free threshold for descendants" applies.


The total taxable amount, less the personal and family tax-free threshold, does not exceed the amount of 18,900 euros in individual taxation and 31,500 euros in joint taxation.

This deduction will be applied by the taxpayer with whom the remaining members of the large family live. When there is more than one taxpayer, with the right to apply this deduction, the amount of the deduction will be prorated equally in the tax return of each of them.

To determine the condition of large family, the situation will be at the date of accrual of the tax, and it must be held in possession of the supporting document issued by the competent body in the matter of the Community of Castile and León.

Pending balances :

In the event that the taxpayer does not have sufficient autonomous community tax liability to apply the total deduction in the tax period in which generate the right to the same, the amount not deducted may be applied in the following three tax periods until the total amount of the deduction is exhausted, if applicable.

When the entire deduction has not been exhausted in these periods, the amount remaining applicable may be requested.


A data capture window must indicate whether there is a large family condition:

You must indicate this in the "Common" column when, in the event of marriage, the large family status corresponds to both spouses. Otherwise, the following will be indicated in the "Holder's" column, indicating the number of people who would have the right to apply the deduction without taking into account the amount of their income: "1" When only the selected holder can apply it; "2" When two people can apply it, etc.