The Magpies face Motherwell on Tuesday, July 16, before jetting off to Iberia to play a brace of fixtures against sides in the top division of the Portuguese League.
First up is Rio Ave on July 20 before taking on Pacos Ferreira three days later.
Pacos Ferreira finished third in the table last season behind Porto and Benfica, while Rio Ave were sixth.
United have also arranged a trip to Bloomfield Road, Blackpool, on July 29 while a Newcastle XI play St Mirren two days later.
In their only home fixture during pre-season, Newcastle will welcome Braga - another club in Portugal's top flight - to St James' Park on Saturday, August 10.