Chapter 3. Taxation of the most common incomes obtained in Spain by non-resident taxpayers
Natural persons and non-resident companies will be considered as IRNR taxpayers to the extent that they obtain income in Spanish territory, as defined in this tax.
If the taxpayer is a resident in a country with which Spain has a contract to avoid double taxation, it must be in line with what is available in it, as in some cases, taxation is lower, and in others, income, if certain circumstances occur, cannot be subject to tax in Spain.
In these cases where the income cannot be taxed in Spain (exempt by agreement) or is taxed with a tax limit, non-resident taxpayers must justify that they are resident in the country with which Spain has signed the Agreement, by means of the corresponding certificate of residence issued by the tax authorities of your country, which must expressly state that the taxpayer is resident within the meaning of the Agreement.
The following are the criteria for the most significant types of income, for which these incomes are understood to be obtained in Spanish territory and the taxation in accordance with Spanish internal regulations and the agreements to avoid double taxation.