Once Boltwood was offered a full professorship and chair of radiochemistry position at Yale in 1910, his career became more academic and he no longer actively pursued research. He was elected to both the United States National Academy of Sciences and the American Philosophical Society in 1911. He was elected to the American Academy of Arts and Sciences in 1913. In 1918, Boltwood became the director of Yale College chemical laboratory. As he took on more responsibilities at the college, he began overseeing the setup of two laboratories – Sloane Physics and Sterling Chemistry. During this time of added stress, he experienced bouts of depression and was forced to take time off to recover from a mental breakdown in 1924. He returned with renewed zeal and continued his work, but fell into periods of depression over the following years. On August 15, 1927, he took his own life in Hancock Point, Maine at the age of 57.