Spanish English translation

Hola, I have to translate into English:

pago a 60 días. And I am not sure if the correct translation from "a" is "at", "to", "in" or "wihthin"

Muchísimas gracias,

Carlota

The correct translation in that specific case it woul be "in"
:D

Payment within 60 days, works too.

Matias is correct but I think Amayo's version is the most common term, i.e., "payment within 60 days".

pago a 60 días.
This refers to deferred payment terms, and would translate as: ...payment at 60 days (from date of invoice/delivery/etc.)

Deferred payment terms always allow for payment to be made at any time on or before the due date starting from the date of the invoice, (except in cases of some large loan transactions such as mortgages which might incur an early payoff penalty due to lost interest).

I've never heard "at"used in this manner. A 60 day invoice would almost certainly allow for early payment. "At" suggests a place or time but not a date. Bills are due "in 60 days; within 60 days; or "...on (a specific date).

The only instance of "at" that I can think of would be "...at the close of business (on specific date)".

True, as a non-native speaker the "in" sounded like the most accurate word to use.. In Argentina (where I live) if we said "payment in 60 days" the payment will happen in exactly 60 days. The "payment within 60 days" it may occur in more or less than 60 days.
But again, I'm no native speaker, so.. Thanks for clarifying that Vicente! :D

I've worked in an accounting department before, and I've never seen an invoice that was meant to be paid on an exact date. When a business provides "net payment days" that means they are willing to finance their client for that amount of time. After this date the payment would be considered late, and late payment fee's may be applied. Therefore, within would be the best translation in my opinion.