to whom it may concern
US /tə huːm ɪt meɪ kənˈsɜːrn/
UK /tə huːm ɪt meɪ kənˈsɜːrn/

1.
A quien corresponda
a formal salutation used when the recipient's name is unknown or when the letter is addressed to an organization rather than an individual
:
•
I started the cover letter with 'To Whom It May Concern' as I didn't know the hiring manager's name.
Empecé la carta de presentación con 'A quien corresponda' ya que no sabía el nombre del gerente de contratación.
•
The official notice was addressed 'To Whom It May Concern'.
El aviso oficial estaba dirigido 'A quien corresponda'.