The above spreadsheet accounts for mailings at the 0.46-cent postal rate since this is the rate for pre-sorted first class.  (First class postage is currently 0.49 cents.  However, when doing mailings with a postage meter given by the USPS and by mailing 500 or more pieces in zip code order at one time, you can qualify for the 0.46-cent pre-sorted first class postage rate.)  This rate applies to double-folded and tri-folded postcards, folded brochures, and letters. Please note that if you will be mailing letters (4- or 8-page sales pieces in a #10 business-size envelope), this will DRASTICALLY INCREASE your cost per mailing piece from the 0.12 cents shown to about 0.35 cents per mailing piece. Be sure to make this change in the spreadsheet if you will be changing up from a brochure or folded postcard mailer to a more expensive mailing piece.

The above spreadsheet accounts for pre-sorted postcards at the current rate of 0.29 cents per postcard.  The normal postage rate currently is 0.34 cents.  However, if you get a postage permit number from a designated USPS location, put your postcards in zip code order, and mail 500 or more pieces, you can qualify for the lower 0.29-cent rate per postcard which is the rate that this spreadsheet is based off of.  Please note that the default cost per piece is listed at 0.12 cents but this is a high cost-per-piece since many postcards can be printed for as low as 0.03 cents per piece depending on your volume of printing.  Getting a lower postcard printing price will bump up your profitablility.