All articles
Margaret Holloway
Margaret Holloway writes about postal addressing standards, CASS certification, and preparing mailing lists for bulk mail.
3 articles
Educational
Do You Need CASS Certification for Address Validation?
CASS is required to claim automation and carrier route postage prices. What the postal rules say, by use case, and when a non-certified API is fine.
Educational
CASS-Certified vs Non-Certified Address Validation
One unlocks postage discounts through PS Form 3553. Both can clean your data. A side-by-side view and when each is the right tool.
Educational
USPS CASS Certification: Complete Guide for 2026
Everything you need to know about CASS certification, postal discounts, and how to save up to 40% on postage.