The best place to eat in Portoferraio itself is Osteria Libertaria, right on the harbor at Calata Matteotti 12 (tel. 0565-91-478), where it's all about the freshest, sizzling fish and Elban specialties like riso nero (risotto blackened with cuttlefish ink). Portions aren't huge; primi cost 10€ and secondi between 10€ and 15€.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.