- Truly is the only acceptable way to spell the adverbial form of the adjective true.
- Truely is not an alternative spelling; it’s a common mistake.
Some adjectives like nice, fine, and blue retain their final e when adding the adverb suffix -ly: nicely, finely, and bluely. With truly, this is not the case.
Is It Truly or Truely?
Although some monosyllabic adjectives ending with “e” retain it when they adopt the -ly suffix to become adverbs, true isn’t one of them.