The methods that work on unaddressed mail
| Method | How it works | Good for |
|---|---|---|
| Campaign-only phone number | A number used only on this mailing. USPS: “Include a phone number in your direct mail that’s used exclusively for the campaign” (USPS Delivers). | Service businesses where customers call |
| QR code to a mailing-only page | The code opens a page that exists only for this mailing, and the page’s visits are your count (USPS Delivers). | Offers redeemed online; booking pages |
| Unique offer code | A word or number printed on the piece that the customer gives you. USPS suggests unique offer or activation codes to track how many codes shoppers use. | Restaurants, retail, anything with a counter |
| The mailed piece itself as a coupon | Collect the pieces that come back in. Count them against the mailing. | Retail and restaurants |
| “How did you hear about us?” | Ask every new customer and write the answer down. Cheap, imperfect, and it catches people who ignore the code. | Everyone, as a cross-check |
Methods one to three are from USPS Delivers’ list. The last two are our advice.
What not to expect
- No piece-by-piece tracking. The Domestic Mail Manual says “No extra services are available with EDDM-Retail mailpieces.”
- Probably no Informed Delivery preview. USPS describes Informed Delivery images as “only provided for letter-sized mailpieces that are processed through USPS’s automated equipment”. EDDM flats are unaddressed and sorted by carrier route, and we found no USPS page that says EDDM is included, so plan on the methods above instead.
How to read the numbers
Count responses you can trace to the mailing and divide by the pieces mailed. Give it time: responses arrive over weeks, not days. Compare the result with the break-even in the response-rates guide before you decide whether to repeat it; and change one thing at a time between drops so you know what moved.