Microsoft has announced plans to invest $10 billion in AI data centers in Sines, Portugal.

As reported by local newspaper Jornal de Negócios, the data centers are being developed in partnership with Start Campus and Nscale.

The investment plans were shared with the publication by Microsoft's president, Brad Smith, during the Web Summit in Lisbon, Portugal, and later confirmed by a Microsoft spokesperson.

The Microsoft-Nscale-Start Campus partnership was first announced in October 2025, with Nscale set to deploy up to 12,600 Nvidia GB300s for Microsoft at the data center campus in Sines.

Start Campus has been in the works for a while. The campus will eventually comprise six buildings with some 1.2GW of IT capacity, but so far, only SIN01 is operational, having launched in January 2025.

The second data center - SIN02 - is currently under development with 180MW of capacity.

A Start Campus spokesperson told DCD that the $10bn investment from Microsoft is "consistent with the ongoing strategic discussions between Microsoft, Nscale, and Start Campus to enable large-scale AI and cloud infrastructure at the SINES Data Campus."

Also with Nscale, Microsoft has signed compute capacity deals in the UK, Texas, and Norway. During Microsoft's latest earnings call, CFO Amy Hood noted that the hyperscaler has dramatically stepped up its data center leasing activity to help alleviate the capacity strain. In its most recent quarter, the company spent $11.1bn on leases alone.

The cloud giant has signed an estimated $60bn in capacity deals with various neoclouds in recent months.

November alone included a $9.7bn deal with Iren and a "multi-billion-dollar" deal with Lambda, expanding on a previously agreed leasing contract.

Other major contracts have been signed with Nebius Group, while Microsoft has long been a major customer of CoreWeave.

The majority of data centers in Portugal are concentrated in the capital city of Lisbon, around 90km from Sines. AtlasEdge, Claranet, Edged, Tata Communications, and Equinix all have a presence in the region.

Sines is also home to the EllaLink subsea cable, with the Medusa, New CAM Ring, Nuvem, and Olisipo cables set to join in the coming years.