Alcañices is a small town in the province of Zamora, in the Castile and León region of Spain. It lies very close to the Portugal–Spain border, not far from the Portuguese town of Bragança.
The town is especially remembered as the seat of the Treaty of Alcañices, signed on 12 September 1297, which defined the border between Portugal and the Crown of Castile. That border is regarded as the oldest in Europe.