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Form 100. Personal Income Tax Return 2021

5.2.1. Children under 18 years of age and adults subject to extended or rehabilitated parental authority

This section only includes children (natural or adopted) who on the date the tax is due are under 18 years of age (unless they live independently of their parents with their consent), or children of legal age who are legally incapacitated and subject to extended or rehabilitated parental authority.

In the data capture window you must provide the following information for each of the children:

  • Surnames and forename

  • The NIF : You will necessarily have to complete the NIF of the children when they are over 14 years old, when, whatever their age, they obtain income and when the children give the right to the deduction for dependent disabled descendants.

  • Date of birth

  • Linking: The corresponding key from those indicated below will be entered in the "Link" box:

    1. Child of both spouses

      No key will be displayed in the "Link" box on the declaration form.

    2. Child exclusively of the "First declarant", provided that he or she does not also live with the other parent.

      On the declaration form, key B will be displayed in the joint declaration and in the individual declaration of the "first declarant".

    3. Child exclusively of the "Spouse", provided that he or she does not also live with the other parent.

      The declaration form will display key C in the joint declaration and key B in the individual declaration of the "spouse".

    4. Child of the "First Declarant" when said child also lives with the other parent.

      This code will be used in the following circumstances:

      1. If the two parents are not married or in cases of legal separation or divorce when there is also shared custody of the children.

      2. In the event that one of the parents has died during the year and the children have lived with both parents until the date of their death, the surviving spouse must include this code D in his or her declaration. In the declaration of the deceased spouse, the code "A" must be entered.

      If you indicate this key “D”, you must also include the NIF, surnames, first name and sex of the other parent. If the other parent does not have a NIF or NIE , they must mark the box provided for this purpose with an X.

      On the declaration form, key D will be displayed in the joint declaration and in the individual declaration of the "first declarant".

    5. Child exclusively of the "Spouse" when said child also lives with the other parent, including cases of shared custody between both parents.

      The declaration form will display key E in the joint declaration and key D in the spouse's individual declaration.

      If you indicate this code “E”, you must also include the NIF, surnames, first name and sex of the other parent. If the other parent does not have a NIF or NIE, they must mark the box provided for this purpose with an X.

  • Disability: In the event that any of the related children can prove a degree of disability equal to or greater than 33%, the recognized degree of disability will be reflected on December 31, recording the corresponding code.

  • Other situations: The "Other situations" box will only be completed when the children are in any of the situations indicated below:

    • Key 2. Legally incapacitated adult son/daughter subject to extended parental authority.

    • Key 3. Son/daughter of the declarant if the latter lives with the other parent without marriage between them. (example: de facto couples with common children who live together).

    • Key 4. Son/daughter of the declarant when situations 2 and 3 occur simultaneously.

  • Adoption date: In the case of adoption, the date (day, month and year) on which registration in the Civil Registry took place shall be indicated or, if such registration is not necessary, the date of the corresponding judicial or administrative resolution.

    In the case of adopted children who have previously been in foster care, the date corresponding to the foster care will also be indicated.

  • Date of death of the child if other than December 31.

  • You must indicate whether or not the child is part of the family unit (example: In de facto couples or when custody is shared, the parent who makes a joint declaration with the children will indicate YES. The other parent will record NO).

  • Income

    • If the child receives an annual income of more than 8,000 euros, excluding tax-exempt income, he/she will tick the corresponding box.

    • If the child files an individual tax return with income exceeding 1,800 euros, he/she will check the corresponding box.

    In the case of de facto couples with common children, and in the case of legal separation or divorce, as long as the custody of the common children is shared, the parent who does not file a joint return with them should not include in their return the children who file a return with income higher than 1,800 euros or those who have income higher than 8,000 euros.

    The program only admits a maximum of four children receiving income.

Once you have completed the above information, by clicking the "accept" button, the program will ask you whether or not you authorize all members of the family unit who have earned income.

With this authorization, the program calculates the individual declarations and the joint declaration.

If you do not authorize, you will have to mark individual taxation.