On 4 March 2019, Spain and the UK (acting on behalf of Gibraltar) signed an international agreement on taxation and the protection of mutual financial interests.
This is the first agreement on Gibraltar with Spain since the 1713 Utrecht Treaty. However it does not imply any modification of the respective legal status of Spain and the UK with regards to sovereignty and jurisdiction over Gibraltar.
It is important to note that this treaty has not yet been ratified by the two respective national parliaments.
The treaty incorporates the provisions for tax residency of natural persons:
1- Whereby natural persons are deemed resident in Spain and Gibraltar according to their domestic law,
(i) They shall be tax resident only in Spain when any of the following circumstances exist:
a) they spend over 183 overnight stays of the calendar year in Spain, from which sporadic absences from either Spain or Gibraltar shall not be deducted,
b) their spouse (not legally separated) or partner and/or dependent ascendants or descendants reside in Spain,
c) the only permanent home at their disposal is in Spain, or
d) 2/3 of their net assets held directly or indirectly are located in Spain.
(ii) They shall be tax resident only in Spain when the above provisions are not conclusive, unless they are able to provide reliable evidence that they have a permanent home to their exclusive use in Gibraltar and remain in Gibraltar over 183 days per annum.
2- Spanish nationals who move their residency to Gibraltar after the date on which this agreement is signed shall in all cases only be considered tax residents in Spain.
3- Non-Spanish nationals who provide proof of their new residency in Gibraltar shall not lose tax residency in Spain within the tax period when the change is made and during the four subsequent years, unless they spend less than one complete tax year in Spain or are registered Gibraltarians (generally British citizens that have resided in Gibraltar for over ten years) that spend less than 4 years in Spain.
4- HNWI, Cat 2, HEPSS or any other equivalent Gibraltar tax schemes shall not by itself constitute proof of tax residency in Gibraltar.
In conclusion
You will be considered tax resident in Spain if you meet any of the conditions where you are deemed resident in Spain (183 days, family ties, permanent home, 2/3 net assets) or you cannot prove that you spend more than 183 days in Gibraltar and own a house at your exclusive disposal there, or if you are Spanish national in all cases (Spanish domestic law currently is more restrictive because nationals do not lose tax residency when moving to a tax haven in the tax period and subsequent four years).
Non-Spanish nationals who have been tax resident in Spain for more than one year and have moved to Gibraltar will be deemed tax residents in Spain for the following four years after they moved. Gibraltarians who have been resident in Spain for more than four years will continue to be resident for four years more.
The rules for Spanish nationals will come into force as of 4 March 2019 if the Treaty is formally ratified.
The rules for non-Spanish nationals will come into force for the taxable periods after the ratification date, the earliest being on 1 January 2020.
Non-Spanish nationals may use this window to consider their position.
In spite of claims for historical Spanish sovereignty over The Rock, Spain (PSOE) has recognized the existence of both a separate tax authority in Gibraltar and the existence of registered Gibraltarians. Moreover, it is proposed that once the treaty is ratified, Gibraltar should be removed from the Spanish blacklist of tax haven jurisdictions.
Source: JC&A Abagados, Marbella