Contaminant exposure of tree swallows, Tachycineta bicolor, nesting in the Great Lakes basin was assessed in 2010 to 2014. Tree swallow nestlings were collected from 69 sites which included multiple sites at some of the 27 Areas of Concern (AOCs) and at nine non-AOC sites. Polycyclic aromatic hydrocarbon (PAHs), polychlorinated biphenyl (PCBs), and polybrominated diphenyl ether (PBDEs) concentrations were measured in nestling stomach contents. Concentrations of PCBs and PBDEs were measured in nestling carcasses. Perfluorinated compounds (PFCs) were measured in nestling plasma. Pooled dietary concentrations of total PAHs were highest at the Rouge River, MI AOC (1,856 ng/g wet weight) and lowest at White Lake, MI AOC (14 ng/g). Nestling PCB concentrations were highest at Waukegan Harbor, IL AOC (geometric mean = 5,908 ng/g) and lowest at a Green Mountain, MN (7 ng/g), a non-AOC. Nestling PBDE concentrations were highest at Torch Lake, MI AOC (72 ng/g) and lowest at Wild Rice Lake, MN (3 ng/g), a non-AOC. Drainages associated with Wurtsmith Air Force Base, MI (non-AOC) had the highest PFC plasma concentrations (1,649 ng/ml) compared to the lowest concentration at Torch Lake, MI AOC (21 ng/ml). Both PAH and PCB concentrations in nestling stomach contents were significantly correlated with concentrations reported in sediment from AOCs in another study. Concentrations of PCBs in mussels measured at AOCs in another study were also significantly correlated with PCB concentrations in tree swallow nestlings. Both PCB and PBDE concentrations were significantly correlated among diet, nestling carcasses, and sibling eggs measured in a companion study.