On 23 May 2011, Aguilar officially joined Club América for the Apertura tournament.
Aguilar made his debut with América on 31 July in a league match against Toluca, which ended in a 1–1 draw.
Upon his arrival Aguilar became a popular player with the club's fans.
He scored his first goal with América in the 90th minute against arch-rivals Guadalajara in the Súper Clásico.

On 26 May 2013, Paul Aguilar won his first title with América after defeating Cruz Azul in the Clausura final, playing in both legs.

On 26 March 2014, Aguilar signed a two-year contract extension with América, which will keep him at the club until 2016.
Aguilar had previously stated publicly that he would like to end his career at América.
Aguilar made his 100th league appearance for América on 30 May in the 4–0 win over Guadalajara.
Prior to the first-leg of the 2014 Apertura semifinal series against Monterrey, it was reported that Aguilar was separated from the squad by manager Antonio Mohamed due to an alleged dressing-room confrontation between the two.
On 23 May 2011, Aguilar officially joined Club América for the Apertura tournament. Aguilar made his debut with América on 31 July in a league match against Toluca, which ended in a 1–1 draw. Upon his arrival Aguilar became a popular player with the club's fans. He scored his first goal with América in the 90th minute against arch-rivals Guadalajara in the Súper Clásico.
On 26 May 2013, Paul Aguilar won his first title with América after defeating Cruz Azul in the Clausura final, playing in both legs.
On 26 March 2014, Aguilar signed a two-year contract extension with América, which will keep him at the club until 2016. Aguilar had previously stated publicly that he would like to end his career at América. Aguilar made his 100th league appearance for América on 30 May in the 4–0 win over Guadalajara. Prior to the first-leg of the 2014 Apertura semifinal series against Monterrey, it was reported that Aguilar was separated from the squad by manager Antonio Mohamed due to an alleged dressing-room confrontation between the two.
Paul Aguilar