YES, Saint Martin (French part) is a French overseas collectivity (COM), so in the Europe zone for your carrier — but beware, the Dutch part Sint Maarten (Philipsburg) is OUTSIDE the EU and roaming for your French carrier. The Alosea Saint Martin eSIM avoids this unique border confusion (open border between 2 countries) — you connect to Orange Caraïbes, Digicel Saint Martin or Dauphin Telecom upon landing at Grand-Case-Espérance (SFG) or Princess Juliana SXM on the Dutch side.