Migliaccio joined Palermo in the summer of 2007, and was strongly wanted by his former coach Stefano Colantuono.

He was also occasionally lined up as a centre-back, first by Davide Ballardini and then, much more regularly, by Walter Zenga, Serse Cosmi and Devis Mangia.

On 31 August 2012, Migliaccio moved on loan to Fiorentina on the last day of the summer transfer window.

In June 2024, Migliaccio returned to Palermo as the club's new "international scout" working alongside the new sporting director Morgan De Sanctis.

On 3 January 2025, both Migliaccio and De Sanctis were removed from their management roles due to Palermo underperforming significantly in the first half of the season.