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RecommendedVerification update: Add provisional addresses to Smarty’s databaseFebruary 16, 2026 Functional options pattern in Go: Flexibility that won’t make future-you sigh loudlyFebruary 10, 2026 Ambiguous address matches: What they are and why compliance teams should careFebruary 3, 2026

Cass vs. NCOALink certification article now live

Cass vs. NCOALink certification article now live

Davin Perkins

Updated October 29, 2025

Tags

Address quality

Address validation

Cass vs. NCOALink certification article now live

We get a lot of questions about USPS CASS certification and how it differs from NCOALink certification. They are both methods of address validation that originate with the USPS. While they look the same and smell the same (probably), they are in fact, very different. Even still, these methods are frequently confused, conflated and equated. So, we decided to cut the confusion and answer all your burning questions about CASS and NCOALink.

Here is some of stuff that future you (who has read the article) already knows:

When you notify the USPS that your address has changed, NCOALink only hangs onto those updates for 4 years.
In order to use NCOALink you must submit a minimum of 100 addresses for validation at a time.
To become CASS-certified, vendors must score 100% accuracy on 150,000 addresses for delivery point coding, eLOT (Enhanced Line of Travel), DPV or DSF2, RDI, and Perfect Address.

Learn all this and much more by checking out the Cass vs NCOALink article here. Future-you will be so proud!

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Verification update: Add provisional addresses to Smarty’s database

With the launch of our latest product feature, US Provisional Address Manual Process, US Address Verification users can now submit new or missing addresses, and we’ll verify them against authoritative databases and add any approved records to our database. Better yet, you won’t need to make any integration changes to see your addresses in your API results, it won’t take longer than 30–60 days, and it won’t cost you anything extra. That’s what we call an all-around win!Let us take the stress of verifying new or missing addresses off your plate so you can focus on what you do best.

Functional options pattern in Go: Flexibility that won’t make future-you sigh loudly

SDK authors live in a permanent tug-of-war:Users want a simple constructor they can paste and ship. Maintainers want room to grow without breaking everybody’s build on the next release. That second part matters a lot right now, because a lot of people are still relatively early in their software careers. Approximately one in three developers has coded professionally for four years or less. That matters because unclear or fragile APIs disproportionately hurt newer developers—they don’t have scars yet.

Ambiguous address matches: What they are and why compliance teams should care

If you’ve ever run into an address that seems to exist in more than one place, congratulations—you’ve discovered the world of ambiguous address matches. They’re the Schrödinger’s cat of location data: valid, yet potentially two distinct locations. This blog will focus on a few key things: What are ambiguous address matches?Why ambiguous address matches matter for compliance and customer serviceHow to handle matches with address ambiguityWhy you should inform your customers of ambiguous address matchesOur final thoughts on ambiguous address matchesWhat are ambiguous address matches?An ambiguous address match occurs when an entered address resolves to two or more valid locations with slight but meaningful differences.

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