Most common letters in 5-letter words Our analysis of more than 8,600 words with 5 letters shows that in order of frequency, the most common letters are: “S”, “E”, “A”, “O”, “R”, “I”, “L”, “T”, “N” and “D”. Consonants make up 6 of the 10 most common letters in 5 letter words. Vowels make up the remaining 4 letters that feature.