Trans. David Grene. Chicago: University of Chicago Press, 1987.
Grene’s translation remains the recommended one for Greek-less readers. While it is not exactly literal, it does the best job of capturing Herodotus’ style (which has shades of Homer, but finally is distinctly his own). Grene also has a vivid sense of the important themes of the work.
From the University of Chicago Press:
In Grene’s remarkable translation and commentary, we see the historian as a storyteller, combining through his own narration the skeletal “historical” facts and the imaginative reality toward which his story reaches. Herodotus emerges in all his charm and complexity as a writer and the first historian in the Western tradition, perhaps unique in the way he has seen the interrelation of fact and fantasy.
Online:
Amazon (recommended edition)
Perseus Project (free online English edition)