Follow the steps to accurately complete your form online.

1. Click the 'Get Form' button to access the form and open it in your browser.
2. Begin filling in the 'Causant' section. Enter the taxpayer's NIF (Número d'Identificació Fiscal) and the date of merit (date of inheritance). Provide the name or social reason of the deceased, as well as the date of death.
3. In the respective fields, indicate the address details such as street name, building number, postal code, municipality, province, and country.
4. Specify if the deceased was obligated to present a declaration of the property tax during any of the four years preceding their death. Indicate the number of interested parties in the succession.
5. Complete the 'Dades del document' section by detailing the type, notary/authority, date of the document, and protocol number.
6. List the people involved in the succession, including their dates of birth and NIFs. Document their relationship to the deceased and any existing disabilities, if applicable.
7. Proceed to fill out sections related to the inheritance assets. List urban and rural properties, their cadastral references, estimated values, and clarify whether they should be included in the taxable base.
8. Capture details of any existing financial accounts, securities, and vehicles. Ensure to document their values accurately.
9. Review all the provided information for accuracy and completeness. Make any necessary corrections.
10. Once complete, you can save your changes, download, or print the form for your records. Additionally, share it with relevant parties if needed.

Start filling out your 2004 ES ATC 660 (Catalan) form online today to ensure smooth processing of your declaration.