Once installed in London, Thomas sought, during the 1830s and 40s, to use knowledge and connections gained at Hopes to increase the firm's visibility in Europe.

During these same years Thomas, along with younger brother John, spent much time promoting Barings in North America, especially the United States.

Entering the 1860s, with the ageing Bates becoming progressively less active, and with new young partner Edward 'Ned' Baring not ready for leadership, Thomas and Russell Sturgis (a second American) assumed command.

While always resistant to heavy involvement in public life, Thomas found time for other finance-related positions, including Chairman of Lloyd's and a director of the Bank of England.

Like his father, he was President of the London Institution and s Fellow of the Royal Society[1] Baring entered Parliament for Great Yarmouth in 1835, a seat he held until 1837, and later represented Huntingdon between 1844 and 1873.