Postcard Mailing

[armenh]

We will be sending out around 5,000 postcards to residential addresses this month. We will follow up after this by sending postcards to many small businesses, this is part of our marketing strategy. The postcards are 4 by 6 so they qualify for the discounted mailing rates. The problem is, I am having a hard time understanding the lower rates USPS allows for pre-sorted mail. Pre-Sorted is 24.5 cents a piece and has a $360 upfront cost for a year.($180 to sign up and $180 annually) When they say pre-sorted what are they referring too? Also, they have even a lower priced option where if it is pre sorted through a computer software. Could anyone shed some light on this and explain to me thoroughly my options?

[hippie_wantab]

presorted I blieve means that it is sorted already by area. (by state, by zip, by street, by house #) So there is less work for them. I looked into this myself years ago, but I cant remember the perticulars