Nathaniel Barratt Smithers (October 8, 1818 – January 16, 1896) was an American lawyer and politician from Dover, in Kent County, Delaware.

Beginning his political career as a Whig, he turned down the nomination to run for Congress in 1844 but did serve as clerk of the State Legislature in 1845 and 1847.

But he became estranged with the mainstream of the Whigs in the state when the party rejected the gradual abolition of slavery and voted in local option concerning alcohol in 1847.

While there he served on the critical Special Committee of Reconstruction and helped turn down the efforts of Arkansas and Louisiana members to be re-admitted.

As the candidate of the Union Party, he was defeated after that one term by John A. Nicholson, a Democrat, in 1864 and returned to private practice.