Ask Randy: Volume 2

Randy Weiler, SPC’s Director of Postal Affairs and Logistics, is here to help you navigate the labyrinth of the USPS. What does it take to efficiently move your projects through the USPS system? What efficiencies can you gain from SPC’s lettershop expertise? Who determines postal increases?

Every month, Randy fields your burning questions about mail and postal affairs in a Q&A format. You can email him at or post a question via Facebook or Twitter using the hashtag #AskRandyUSPS. We post the questions and his answers each month both here on the SPC blog and on social media.

1: What is the difference between Enhanced Carrier Route Letters and Every Door Direct Mail?

Enhanced Carrier Route (ECR) Letters and Every Door Direct Mail (EDDM) are both types of mail that are based on carrier routes. Just like it sounds, a postal carrier route is a group of addresses that a mail carrier delivers to. Each of the ~600,000 carrier routes in the US are identified by a 4-digit code attached to the end of a 5-digit ZIP Code (keep in mind, this is different from ZIP +4 Codes). The number of residential, business, and total addresses included in a carrier route varies for each carrier route.

The main difference between these two types of mail is that EDDM pieces are mailed to an entire carrier route, whereas ECR Letters can be mailed to a partial carrier route. However, if we take a more detailed look at each type of mail, you’ll see additional differences in the design and execution of the mailing.

First we will focus on EDDM. EDDM does not use a mailing list. Instead, the carrier routes are chosen based on location and other criteria such as number of residential addresses, number of business addresses, number of total addresses, age, average size of household, and average household income.

The size of an EDDM piece must qualify as a Flat instead of a Letter by exceeding one or more of the following dimensions: 10.5” long, 6.125” high, or 0.25” thick (but must be smaller than 15” long, 12” high, and 0.75” thick, and weigh less than 3.3 oz.). An EDDM piece cannot contain any personal information—the piece must have a generic address block, addressed to “Postal Customer,” “Residential Customer,” or “PO Box Customer.” EDDM flats will follow the pricing structure of Saturation ECR Letters.

With ECR Letters, a mailing list is required. To qualify as high density, high density plus or saturation ECR prices, the data must be sorted to carrier routes in walk sequence (the order of delivery for each delivery point in a carrier route). Pieces mailed at high density prices must have a minimum of 125 pieces per carrier route. Pieces mailed at high density plus prices need a minimum of 300 pieces per carrier route. Lastly, pieces mailed at saturation prices deliver to a minimum of 90% of active residential addresses or 75% of total active delivery addresses in a carrier route. Saturation ECR Letters will have the deepest postal discounts of the ECR postal rates.

ECR Letters follow the USPS Letter size requirements. Pieces that qualify as Flats can still mail as ECR, with different postage rates than ECR Letters (click here for more information on postage rates). These pieces can include personal information like a personalized address block and variable personalized messaging.

The advantages of EDDM and ECR Letters are deep postal discounts on highly localized bulk mail. Determining which of the two methods to use will come down to the mailing’s personalization, list availability, and size.

2: When should I consider commingle mail entry?
  • Any National Letter sized job with mail quantities less than 150,000 pieces
  • Any job with low quantities of pieces qualifying for 5-digit automation after presort

Two ways to qualify for deeper postal discounts are entering mail at the NDC or SCF level, or bundling and sending mail with the same 5-digit ZIP Code. Typically, mailings of small quantities that are spread out around the country do not have much mail qualifying for NDC or SCF entry. This, combined with the low quantity of 5-digit makes them prime candidates for commingle. Commingling combines individual pieces of mail from multiple mail owners and sorts them to achieve greater density of mail going to SCFs and NDCs. Consider that Origin entry AADC letter mail postage is $.274 per piece—commingle letter mail should net out a savings of close to $.02 per piece. This savings includes the cost of commingle services, freight and handling. Additionally, in-home delivery with commingle is faster than Origin entered mail because delivering to an NDC or SCF bypasses the sorting and transportation the USPS would have to perform on Origin entry mail.

3: What is your favorite dessert?
Answer: Coconut Cream Pie
4: What is the cost to open a new permit?
Answer: $225

(Effective January 21, 2018) Currently it costs $225 to open a permit. Annual fees are waived if the mailings submitted to mail using the permit contain 90% or more Full-Service pieces.


Randy Weiler
Director Postal Affairs and Logistics

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