PDF Letter Order

Windowed and Windowless Letters can be sent by submitting only a PDF URL via the API. Send each recipient’s address in the recipients array, not in the PDF. thanks.io prints the address for you:

Windowed letters (/send/windowedletter): the recipient’s name and address are printed in the upper-left area of page 1, where they show through the envelope window.
Windowless letters (/send/windowlessletter): the address is printed on the envelope, so your PDF can use the full page.

For windowed letters, leave the upper-left address area of page 1 blank. Do not put a recipient address in your PDF. An address already in the PDF is printed over, and the recipient receives a letter with two overlapping addresses.

  curl -X POST "https://api.thanks.io/api/v2/send/windowlessletter" \
    -H "Content-Type: application/json" \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -d '{ 
      "pdf_only_url": "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf",
      "recipients": [
        {
          "name": "Current Resident",
          "address": "123 Main Street",
          "city": "Fake City",
          "province": "NY",
          "postal_code": "55555",
          "country": "US",
          "custom1": "Example Custom 1",
          "custom2": "Example Custom 2",
          "custom3": "Example Custom 3",
          "custom4": "Example Custom 4"
        },
        {
          "name": "Jane Doe",
          "address": "456 Another St",
          "city": "Fake City",
          "province": "NY",
          "postal_code": "55555",
          "country": "US"
        }
      ]
    }'

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