In this article, we explain what CASS is and why it’s used, read on to find out more.

Across the US, the United States Postal Service (USPS) is relied upon to a colossal extent. USPS delivery staff covers more than 148 million homes and almost 13 million business addresses across the country. That is an incredible amount of ground to cover, and deliveries take place – according to USPS – at least six days out of seven. However, as a result of dirty data concerns, CASS Address Standardization was brought in to help simplify address crunching.

CASS allows USPS to standardize the way that mail. This system is incredibly important to American business administration. Let’s take a closer look.


CASS stands for Coding Accuracy Support System. USPS designed this model to ensure that all addresses used in the US mail system follow the same pattern. This is, ultimately, to reduce the risk of errors and to avoid mis-mailing.

The formatting for CASS is fairly straightforward. CASS data follows the pattern:

  • Address/house number
  • Name of street
  • Name of city
  • Name of state and ZIP code

Effectively, these are the broadest levels at which addresses can standardize. Essentially, a certified data handler or system will check all information against USPS records. This system will need to ensure that all information files correctly, that there are no mistakes, and that data is easy to source.

As you may expect, this will require platforms working with USPS data to pass the service’s verification.


For address data to pass USPS’ muster, a data handler will need to adhere to both DPV and LACS.

DPV refers to Delivery Point Validation. Essentially, this means that your system communicates with USPS to ensure that data correlates at both sides. Therefore, USPS will confirm whether or not said data is valid. This ensures that businesses are delivering to and are contacting correct addressees.

All of this helps ensure there is no confusion on either delivery to an agent or if your USPS package is delivered to the agent or not.

LACS, meanwhile, revolves around emergency services. While this may not concern all businesses, a LACS record indicates that data is current and valid. LACS stands for Locatable Address Conversion System and is the latest overhaul for US emergency services’ contact data.

CASS address verification ensures that data captured and held by a business is standardized to USPS’ demands. It is, crucially, a compliance factor.

See how WinPure helps you with address verification and standardization.


CASS Address Standardization matters simply because, without it, businesses cannot reach their customers and contacts. Providing USPS agrees that the data you hold is compliant, you can be sure that your contact information is valid to use.

Incorrect postal data costs our economy a huge amount of money. According to a white paper produced by Pitney Bowes, returned mail costs the postal service $1.2 billion at the residential level. The impact on business mail tapers out at around $20 billion.

Data shows that direct mail is still important for businesses, particularly when it comes to building and maintaining leads. Around 73% of US consumers surveyed confirm they prefer advertising contact through traditional mailboxes. While email marketing is proving to be hugely impactful, ‘snail mail’ still provides a return investment of around 29%, on average.

CASS is, therefore, crucial to adhere to. If mail is going missing as a result of dirty data, businesses stand to miss out on crucial leads. It also takes sizable chunks out of the economy in general.

There is also the matter of simplification. Ensuring that your data is CASS compliant means less need to rely on multiple workflows and databases. A single CASS system will ensure that all your contact data is present, correct, and in line with USPS standards.

Many businesses may also find that they can save money, on the whole, by using bulk CASS processing through USPS. To access such discounts and savings, however, business owners must take charge of their data cleaning.


CASS certification is not difficult to arrange. However, to ensure that your information is compliant with USPS standards, you must use software that follows such guidelines to the letter.

Crucially, businesses that do not use software with CASS sorting as a feature will have to analyze addresses manually. Depending on the industry you operate in, this means you may have to work through hundreds of thousands of records.

Software that is certified through CASS will automate the process. However, your business software must have access to relevant data in the first instance. If it does not have the information to fill out CASS forms, it cannot ensure your records are fully compliant.

That is why it is important to find software that collates and sorts data but helps break down siloes. Breaking down said siloes in line with CASS will ensure mail reaches the right people at the right time.


CASS processing follows a straightforward procedure of cleaning and correlation. Data cleaning software will generally follow a four-point process to ensure that all CASS information is correct and compliant.

Various reports suggest that mail continues to go missing in some cases. Some reports indicate that, in New York City alone, more than 90,000 packages are mis-sent each day. Other records claim that around 3% of US mail goes missing, period.

These statistics may seem vague on the surface. However, it is clear why USPS wishes to tighten up data processing, for reasons explored above.

The four steps in the processing chain, generally, are as follows:

  • CASS Standardization – where data formats to USPS’ exacting standards. This enables data cleaning software to fill out gaps in forms where possible. However, said data will need to be available at the user company’s disposal.
  • Correction – at this stage, any data that is incorrect or mistyped will be adjusted. This also covers missing ZIPs. As human error impacts around 60% of all dirty data issues, this stage is crucial
  • Updates – software communicates with USPS to ensure that the latest address a business has on file is correct. If it is not, the software makes necessary changes.
  • Validation – at this stage in proceedings, providing an address is correct; it is checked to ensure it is valid to mail to.

All four of these steps in the CASS process ensures that a business has the correct information in their database. Therefore, a company can continue to mail to customers, build leads and more.


Not only does WinPure actively break down duplicates and siloes, but it also offers full USPS certification. Your business can effectively automate data collection and customer mailing at full accuracy.

While statistics show there are still a few problems regarding mis-posting in the US, USPS is working hard to fix such issues. With the support of WinPure, your business can help provide a solution to ensure customers receive the mail they expect. What’s more, you will also save money on bulk mail and take advantage of high accuracy lead building.

CASS Address Standardization is a vital facet of all modern business data solutions. Why not take a closer look at WinPure Clean & Match for more information?


Written by Farah Kim

Farah Kim is a human-centric product marketer and specializes in simplifying complex information into actionable insights for the WinPure audience. She holds a BS degree in Computer Science, followed by two post-grad degrees specializing in Linguistics and Media Communications. She works with the WinPure team to create awareness on a no-code solution for solving complex tasks like data matching, entity resolution and Master Data Management.

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