How to Write Thank You in Spanish
To write thank you in Spanish, simply write the word, “gracias,” to express gratitude. You can add emphasis by adding the word “muchas” before it. For a more formal way to say thank you, write, “Estoy agradecido,” which means “I am grateful.” If you are referring to a thank-you note, use the term “agradecimiento.”
Write the word "gracias". Gracias is the word for thank you in Spanish. It can be used in almost any context, in order to express gratitude. The word gracia in Spanish means "grace", so gracias literally translates as "graces" or "lots of graces". The word gracias is pronounced as "grass-ee-ass" by Spanish speakers in Latin America, and as "grath-ee-ass" in Spain. Emphasize your thanks by adding "muchas" or "muchísimas". If you wish to say something along the lines of "thank you very much" or "thanks a lot", you can either say muchas gracias or muchísimas gracias. Write "I am grateful". "I am grateful" in Spanish is written as "estoy agradecido" if you are male, or "estoy agradecida" if you are female. Write "thank you in advance". The phrase "thank you in advance" is written as "con gracias anticipadas" in Spanish. Write "thank you sir" or "thank you madam". "Thank you sir" is written as "gracias señor" in Spanish. "Thank you madam" is written as "gracias señora". Don't forget to put the diacritical tilde on the "n". Write "thank you again". To say "thank you again", for example, at the bottom of a letter, you can write "con gracias repetidas". Write "thank-you" as a noun. If you want to write "thank-you" as a noun, you would use the word "agradecimiento". For example, the phrase "she sent a thank-you for the wedding gifts" would be translated into Spanish as "ella envió una nota de agradecimiento por los regalos de boda". 
Write the word "gracias". Emphasize your thanks by adding "muchas" or "muchísimas". Write "I am grateful". Write "thank you in advance". Write "thank you sir" or "thank you madam". Write "thank you again". Write "thank-you" as a noun. 