Is mail service usually slower over the weekend than during the week day?

why, and how this depends?



if you send a letter with a 1st class stamp in the mail...on friday..how likely is it to arrive in same city on SATURDAY? or will most likely not arrive till monday,,since it is friday night sorting and not a regular week day night?

how depends and why?



thanks for your answers!Is mail service usually slower over the weekend than during the week day?
our P.O. is only open 1/2 day on sat.. insufficient time to case mail and load truck %26amp; deliver same day.Is mail service usually slower over the weekend than during the week day?
we don't have weekend service here. :)