Championship winners Reading will take on League One runners-up Sheffield Wednesday as part of their pre-season tour of Portugal.
The Berkshire club will face the Owls, who were recently promoted from League One, at the Quartiera Stadium in Vilamoura on July 24.
Brian McDermott's Royals take on local side Quarteirense three days earlier, with Primera Liga side Olhanense lined up for July 27.
The Algarve-based outfit are managed by Sergio Conceicao, formerly of Inter Milan and Lazio.
The Royals return to England on July 28 in preparation for the new Premier League season.