to the letter

to the letter (not comparable)

1. (idiomatic) Literally, exactly, following the rules as written.

   You should follow what your boss said to the letter. Otherwise, you'll lose your job.

   • 2011, Phil McNulty, “Euro 2012: Montenegro 2-2 England”, in BBC News‎:

     Capello warned his players that caution was not an option as they went in search of the result that would take England to Euro 2012. And his message was carried out to the letter in the opening exchanges as England played with a tempo and threat Montenegro struggled to subdue.

• without fail

• by the book
• by the numbers
• letter of the law
• literalism