Confirming that an Address is Valid

Getting Started

This guide explains how to validate and clean up your address list using LetterStream’s built-in tools and visual indicators. You’ll learn how to identify and correct problematic addresses to improve mailing accuracy.

In This Article

Using Address Validation Tools

For the most accurate results, we recommend using one of LetterStream’s address clean-up tools:

  • NCOA (National Change of Address): Helps identify recipients who have moved within the last 18 months.
  • CASS (Coding Accuracy Support System): Verifies that addresses are complete, correctly formatted, and deliverable.

These tools help ensure that your mail reaches the intended recipients by identifying outdated or incorrect address data. Click here for more information.

Identifying Bad or International Addresses

When you upload an address list and build a job in your LetterStream account:

  • The system automatically flags potentially problematic addresses.
  • These addresses appear highlighted in pink for easy identification.

Common issues include:

  • Incomplete or incorrectly formatted information
  • Possible international addresses

Note: Recipients that are highlighted in pink may have international postage applied depending on the job type.

Limitations of System Checks

While the system automatically checks key components of each address, it does not catch every issue. To ensure comprehensive validation, especially for large or important mailings, use the NCOA or CASS tools.