Line 3 of the Bilbao metro is a rapid transit line in Biscay, Basque Country, Spain.

It is 5.9 km (3.7 mi) long and connects Etxebarri and the Uribarri and Otxarkoaga-Txurdinaga districts in Bilbao with the city center.

[2] Unlike the two other lines of the system (which are operated by Metro Bilbao S.A.), line 3 is operated by Euskotren, which runs it as part of the Euskotren Trena network.

[5] As the line is part of the wider Euskotren Trena commuter/interurban railway network, most trains on the line continue beyond the termini of Matiko and Kukullaga.

[4] The line shares rolling stock with the rest of the Euskotren Trena network.