What Is CASS Certification?
CASS stands for Coding Accuracy Support System. It is a USPS certification program that validates and standardizes postal address data to ensure that addresses are formatted correctly, assigned accurate delivery point codes, and conform to USPS postal addressing standards.
CASS-certified processing does the following to your address data:
- Standardizes address format: Corrects abbreviations, fills in missing address elements (ZIP+4, carrier route, delivery point barcode), and reformats addresses to USPS standard notation
- Validates address existence: Confirms that the address physically exists and can receive USPS mail delivery
- Assigns delivery point codes: Adds ZIP+4 and carrier route codes required for automation-rate postage discounts
- Corrects common errors: Fixes misspelled street names, incorrect city-state combinations, and missing directional indicators
- Required for automation rates: USPS automation postage discounts require that mailing lists be processed with CASS-certified software before mailing
Without CASS processing, bulk mail campaigns cannot qualify for the lowest postage rates, and mailpieces with improperly formatted addresses are more likely to be missorted or returned as undeliverable.
What Is NCOA Processing?
NCOA stands for National Change of Address. The NCOA database is maintained by the USPS and contains address updates for individuals and businesses who have filed a Change of Address form within the past 48 months.
NCOA processing matches your mailing list records against this database and updates the postal address for any contact who has moved and filed a change of address. It does not create new address data. It updates existing records where a USPS-confirmed move has occurred.
What NCOA processing does to your mailing list:
- Updates moved addresses: Replaces old addresses with current USPS-confirmed forwarding addresses for contacts who have relocated
- Flags unresolvable moves: Marks records where a move was filed but no valid forwarding address is available, allowing you to remove or quarantine those records
- Reduces undeliverable mail: Significantly reduces mailpieces returned as undeliverable due to outdated recipient addresses
- Supports recency of contact data: Especially important for mailing lists that have not been refreshed in 12 months or more, where address decay from consumer and business relocation is measurable
The USPS requires that all NCOALink processing use CASS-certified address matching software. The two processes are therefore used together as a standard direct mail data hygiene workflow.
Why CASS and NCOA Are Required for Direct Mail
For any organization running bulk direct mail campaigns, CASS and NCOA processing are not optional quality improvements. They are operational requirements with direct postage and deliverability consequences.
Postage cost reduction: USPS automation postage rates require CASS-certified address processing. Without it, your mailing cannot qualify for the discounted rates available to automation-rate bulk mailers. On large mailings, this cost difference is material.
Undeliverable mail reduction: Industry estimates suggest that mailing lists that have not been NCOA processed in the past 12 months may contain 5 to 15 percent outdated addresses due to consumer and business relocation. Each undeliverable mailpiece represents both wasted production cost and postage spend with zero delivery value.
Mail processing accuracy: USPS automated mail processing equipment reads delivery point barcodes and carrier route codes to sort mail. CASS processing adds these codes and ensures they are accurate, reducing missort rates that result in delayed or misdirected delivery.
USPS compliance: For organizations sending at automation rates, USPS standards require that address lists be CASS-certified and NCOA processed within 95 days of the mailing date. Non-compliance can result in postage rate adjustments on audited mailings.
For organizations sourcing new mailing lists rather than processing existing files, all postal address data in our consumer direct mailing lists and business direct mailing lists is already CASS and NCOA processed before delivery.
What You Get: CASS and NCOA Processing Output
CASS Processing Output
- Standardized address records conforming to USPS formatting standards
- ZIP+4 code assignment for every deliverable address
- Carrier route code assignment for automation rate qualification
- Delivery point barcode ready for mail production
- Address correction report showing all records modified
- Undeliverable record identification and flagging
NCOA Processing Output
- Updated postal addresses for all records matched against the USPS NCOALink database
- Move type coding: individual, family, or business move
- Forwarding address record for matched movers
- Unresolvable move flag for records where no valid forwarding address exists
- Processing certificate confirming NCOA compliance and processing date
- Summary report showing match rate and update statistics
Combined CASS + NCOA Output
- Fully standardized, NCOA-updated mailing list ready for automation-rate bulk mailing
- Deliverability screening report
- USPS processing certificate for postage rate qualification
- Suppressed records file for removed undeliverable addresses
How CASS and NCOA Processing Works
Step 1: Submit Your Mailing List. Provide your contact file in a standard format. We review the address field structure and confirm the processing requirements before starting.
Step 2: CASS Processing. Your address records are run through CASS-certified software that standardizes each address, validates deliverability, and assigns ZIP+4 and carrier route codes. Undeliverable addresses are flagged.
Step 3: NCOA Processing. Your CASS-processed records are matched against the USPS NCOALink database. Moved records are updated with current forwarding addresses. Non-forwardable move records are flagged for suppression.
Step 4: Delivery of Processed File. You receive your cleaned, standardized, and updated mailing list along with a processing report and USPS compliance certificate. The file is ready for mail production and automation-rate postage qualification.
Contact our direct marketing list brokers to arrange CASS and NCOA processing for your mailing list.
How Often Should You Process Your Mailing List?
USPS guidelines recommend that mailing lists used at automation rates be NCOA processed within 95 days of the mailing date. For organizations running multiple campaigns per year, this means:
- Quarterly mailers: Process your list at least once per quarter before each campaign
- Annual mailers: Process your list within 95 days before each annual campaign date
- Ongoing database management: For large consumer or business databases used across multiple campaigns and channels, running CASS and NCOA as part of a regular data hygiene schedule reduces accumulated address decay
Address decay rates are approximately 10 to 15 percent per year for consumer lists and somewhat higher for B2B lists, due to business relocations, closures, and ownership changes. Regular NCOA processing is the most cost-effective way to maintain address accuracy over time.
Compliance and USPS Standards
USPS Automation Rate Requirement: All mailings claiming automation rates must be produced from address lists processed with CASS-certified software. The USPS can audit mailings and assess postage rate adjustments for non-compliant address processing.
NCOALink Compliance: All NCOALink processing must use CASS-certified software. Processing must be completed within 95 days of the mailing date for USPS compliance. A processing certificate is issued confirming the compliance date.
CASL Compliance (Canada): For mailing lists used in Canadian direct mail campaigns, address accuracy and currency are best practices for deliverability, though Canadian address standardization follows Canada Post standards rather than USPS CASS.
Pricing and Service Options
CASS and NCOA processing through Prospects Influential is priced based on file size and processing type:
CASS Processing Only: Address standardization, validation, and delivery point code assignment for files requiring postage rate qualification without NCOA update.
NCOA Processing Only: Change-of-address matching and update for files where address standardization has already been completed.
CASS + NCOA Combined Processing: Full address hygiene workflow combining standardization, validation, and change-of-address update in a single processing run. Recommended as the standard workflow before any direct mail campaign.
Contact our brokers for a no-obligation quote based on your file size and processing requirements.
Who Uses CASS and NCOA Processing
- Direct mail marketing agencies preparing client mailing lists for bulk campaigns
- In-house marketing teams running branded direct mail to customer or prospect files
- Nonprofit organizations maintaining donor and prospect mailing lists
- Insurance and financial services companies sending policy documents and prospect mail
- Retailers running catalog or promotional direct mail campaigns
- Political campaigns preparing voter contact files for direct mail outreach
- Real estate companies maintaining property owner and agent contact lists
- Any organization claiming USPS automation postage rates on bulk mailings
Why Choose Prospects Influential for CASS and NCOA
Prospects Influential combines over 30 years of direct marketing data expertise with CASS-certified address processing capability for clients across the US and Canada. We operate from offices in West Vancouver, BC and Bellingham, WA.
Why clients use us for address processing alongside list brokerage:
- Single-source list and data services: Source a new mailing list and have it processed in one engagement, or bring your existing file for processing only
- CASS-certified processing: All address processing uses USPS-certified software that qualifies your file for automation postage rates
- NCOA compliance certificate: Every processed file includes a USPS compliance certificate confirming processing date for postage rate qualification
- US and Canada coverage: Address processing available for both US and Canadian mailing files
- One-on-one specialist support: Work with an experienced data team that advises on file preparation, processing options, and deliverability improvement
- No-obligation quote: Processing quote provided based on your file size and requirements before any work begins
Frequently Asked Questions
-
What is CASS certification and why does it matter for direct mail?
CASS (Coding Accuracy Support System) is a USPS certification for address validation and standardization software. CASS processing ensures that addresses in your mailing list are correctly formatted, deliverable, and assigned the delivery point codes required for USPS automation postage rates. Without CASS processing, mailings cannot qualify for automation-rate discounts.
-
What is NCOA processing?
NCOA (National Change of Address) processing matches your mailing list against the USPS database of address updates filed by individuals and businesses who have moved within the past 48 months. It updates your records with current forwarding addresses and flags records where no current address is available.
-
Are CASS and NCOA required for bulk mail?
Yes. USPS automation postage rates require that address lists be CASS-certified processed. NCOA processing is required to be completed within 95 days of the mailing date for compliance with USPS address hygiene standards.
-
How often should I run CASS and NCOA on my mailing list?
USPS guidelines require NCOA processing within 95 days of each mailing date for automation-rate compliance. For ongoing databases, quarterly processing is a common standard to maintain address accuracy between campaigns.
-
What is the difference between CASS and NCOA?
CASS validates and standardizes postal address format and confirms that an address can receive USPS mail delivery. NCOA updates the address for recipients who have moved and filed a change-of-address with the USPS. Both are typically run together as part of a complete address hygiene workflow.
-
Can CASS and NCOA processing reduce my undeliverable mail rate?
Yes. Combined CASS and NCOA processing typically reduces undeliverable mail rates significantly by correcting address formatting errors, identifying non-existent addresses, and updating records for contacts who have relocated.
-
How long does CASS and NCOA processing take?
Processing time depends on file size. Most standard files are processed and returned within 2 to 4 business days. Larger files or those with significant address quality issues may take slightly longer.
-
Do you provide a USPS compliance certificate with processed files?
Yes. Every file processed through NCOA receives a compliance certificate confirming the processing date, which is required for USPS automation postage rate qualification.
-
Can you process Canadian mailing lists?
Yes. We provide address standardization and hygiene services for Canadian mailing files following Canada Post address standards. Canadian address processing is available alongside or separately from US CASS/NCOA processing.
-
What file format should I submit for address processing?
We accept standard data file formats including CSV, Excel, and delimited text files. Contact us to confirm the field requirements and submit your file for a no-obligation quote.