Address Cleanup

Getting Started

LetterStream offers two address cleanup services—CASS and NCOA—to help standardize and verify mailing addresses according to USPS requirements. Both tools ensure proper formatting and accuracy, with NCOA offering the added benefit of updated address information for recipients who have recently moved.

In This Article

• CASS (Coding Accuracy Support System)
• NCOA (National Change of Address)
• File Requirements
• Downloading Cleaned Files
• Delivery Point Validation

CASS (Coding Accuracy Support System)

• Cost: $19.95 base + $0.005 per recipient
• Includes:
  • Converts all text to uppercase
  • Formats address data into a single line
  • Corrects spelling of city names
  • Adds ZIP+4 codes when a valid address is provided
  • Will not add missing name or company name information
• Ideal for: Ensuring address accuracy and format compliance

NCOA (National Change of Address)

• Cost: $29.95 base + $0.008 per recipient
• Includes all CASS features, plus:
  • Provides updated addresses for recipients who moved within the last 18 months
• Ideal for: Maintaining an up-to-date address list for more reliable mail delivery

File Requirements

• Upload must be a properly formatted .csv file (generated via Microsoft Excel)
• Name and company name fields must already be included—these will not be added
• Addresses should include at least: recipient name, street address, city, state, and ZIP

Downloading Cleaned Files

You will receive and email once your address list is available for download. Once your cleanup process is complete:

1. Log into your LetterStream account
2. Click on the job name
3. Click the Download button to retrieve your updated address file

On this same page, you will have a list of the possible results and what they mean.

Delivery Point Validation

Included in both CASS and NCOA, Delivery Point Validation (DPV) determines whether the individual delivery point exists at the specified street address. It checks your data against USPS records to confirm the address is complete and accurate down to the delivery point level.

DPV validation includes:

• Verifying that the house or building number falls within the USPS-approved number range for a specific street
• Ensuring that the street, city, and ZIP code combination is recognized by USPS
• Reducing undeliverable or returned mail by validating the complete delivery address

These services help you maintain accurate and USPS-compliant mailing lists, ultimately improving the effectiveness of your mail campaigns.