In recent months, Spain has been at the centre of European migration policy debate. Whereas the breach of the national border at Ceuta has reopened the questions of migrant instrumentalisation against Europe, border security and asylum, the country’s regularisation exercise has concerned an incomparably higher number of people. It is the regularisation exercise that this In Brief focuses on.

Between 16 April and 30 June 2026, the Spanish government opened a pathway towards legal residence status to more than a million non-EU nationals already residing in the coun-try. Irregular migrants were eligible for temporary residence permits if they could prove that they had arrived in Spain before December 2025, lived in the country for at least five months and had no criminal record. These two conditions aimed to exclude economically inactive migrants and discourage non-EU nationals from travelling to Spain after the announcement of this measure.

The measures follow the example not only of Spain’s past regularisations (1986, 1991, 1996, 2000, 2001 and 2005) but also of large-scale mass regularisations undertaken by other Eu-ropean countries—including Belgium (2000), France (1981/82, 1997/98), Ireland (2022), Italy (1990, 1998, 2002 and ongoing since 2020), Greece (1998, 2001, 2005, 2024), and Portu-gal (2007, 2020).

The present regularisation conducted by Spain is likely the EU’s largest ever. It has been paralleled and even, perhaps, surpassed in scale only by the effects of the accession of eight Central and East European countries to the EU on 1 May 2004. These countries’ join-ing the EU resulted in de facto regularisation of stay (not necessarily the employment) of large numbers of their citizens already residing and illegally working in the existing member states up until 2004. Unfortunately, no robust estimate is available for the number of nation-als of the acceding states who resided in the EU-15 at the time of the 2004 enlargement.

Returning to Spain, and regularisations more broadly, what are the economic impacts and legal implications of regularisation exercises?