Bulk mail broadly refers to mail that is mailed and processed in bulk at reduced rates. The term does not denote any particular purpose for the mail; but in general usage is synonymous with “junk mail”.

For example, the United States Postal Service (USPS) defines bulk mail broadly as “quantities of mail prepared for mailing at reduced postage rates.” The preparation includes presorting and placing into containers by ZIP code. The containers, along with a manifest, are taken to an area in a post office called a bulk-mail-entry unit. The presorting and the use of containers allow highly automated mail processing, both in bulk and piecewise, in processing facilities called bulk mail centers (BMCs).

In 2009, the USPS announced plans to streamline sorting and delivery, which would recast the BMCs as “Network Distribution Centers”.[1][2]

So all this means every three months they change the rules! This is how it is done as of October 26, 2012:

First job is to make your envelop. I have an example but they said I did it incorrectly. You MUST put before the name “Current Resident or”. All else is correct on the envelope. Bulk Envelope

After you have done your envelopes sort by zip code. All members currently in our branch but two have 945 and the other two go to another area.

It is very important you get to the post office bulk department before 2 pm. Take the mailings to the main Danville post office which is on Tassahara Road.

On arriving complete the bulk form. This is a copy Bulk Form. AADC is referring to our 945 zip code. Mixed AADC refers to outside 945. Complete the second page of the form as shown on page 2 as shown: Page 2 of form.

They will give you a receipt.