How to Say "yours truly" in Spanish
The Spanish word for “yours truly” is “servidor” — C1 level.

Examples
Me despido de usted, su afectísimo servidor.
I take my leave of you, yours truly (or: your most affectionate servant).
Aquí, su servidor, haré lo que sea necesario.
Here, yours truly (I), will do whatever is necessary. (Often used ironically)
A Polite Way to Say 'I'
This usage is a historical way of showing respect by calling yourself the other person's 'servant.' It functions as a very humble replacement for the pronoun 'yo' (I) or as a closing signature.
Using it Casually
Mistake: “Using 'servidor' to refer to yourself in everyday conversation.”
Correction: Only use this meaning in extremely formal written correspondence or if you want to sound old-fashioned/sarcastic. Stick to 'yo' for 'I'.
Related Translations
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