Jose Luis Perez-Serano (Perez) appeals the sentence he received after he pleaded guilty to illegal reentry. Perez’s argument that the sentencing provisions in 8 U.S.C. § 1326(a) and (b) are unconstitutional is foreclosed by Almendarez-Torres v. United States, 523 U.S. 224, 118 S.Ct. 1219, 140 L.Ed.2d 350 (1998). See Apprendi v. New Jersey, 530 U.S. 466, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000); United States v. Dabeit, 231 F.3d 979, 984 (5th Cir. 2000); see also Shepard v. United States, — U.S. -, -, 125 S.Ct. 1254, 1262, 161 L.Ed.2d 205 (2005).

The parties agree that the district court committed error that is plain when it enhanced Perez’s sentence based on facts that were not found by a jury or admitted by Perez and when it sentenced Perez using Guidelines that it believed were mandatory. See United States v. Mares, 402 F.3d 511, 520-21 (5th Cir. 2005), petition for cert. filed (U.S. Mar. 31, 2005) (No. 04-9517); United States v. Valenzuelar-Quevedo, 407 F.3d 728, 731 (5th Cir. 2005). Perez, however, fails to meet his burden of showing that the district court’s error affected his substantial rights. See Valenzeuela-Quevedo, 407 F.3d 728, 731; see also Mares, 402 F.3d at 521. Therefore, the district court’s sentence is AFFIRMED.