AddressVerify: A Smarty Alternative With Property Intelligence
Smarty is one of the best postal validation and autocomplete APIs on the market. If you also need to know whether an address is a house, what kind, and what it is worth, that is the gap AddressVerify fills.
Let us be fair to Smarty, because the honest version matters. Smarty (formerly SmartyStreets) is a fast, developer-friendly address platform built on USPS CASS-certified data, with US and international coverage, rooftop geocoding, and one of the cleaner autocomplete experiences available. For pure deliverability, presort, and address standardization, it is a genuinely good tool and you should not rip it out for the sake of it.
The reason teams still search for a Smarty alternative is almost never "Smarty is bad at addresses." It is that a validated address only answers half of the question. Smarty confirms the mail will arrive. It does not tell you that the address is a single-family home rather than a warehouse, a duplex, or a PO box, and it has no concept of what the property is worth. For lead qualification, home services, solar, roofing, insurance, and real estate, that second half is the whole point.
AddressVerify is built for that second half. One JSON call returns deliverability plus the residential property picture: home type, estimated value, and the full expanded block of beds, baths, lot size, year built, tax assessment, and listing history. This page is an honest comparison of where each tool fits.
Smarty vs AddressVerify
An honest, capability-by-capability comparison. A green check marks where each tool leads.
| Capability | Smarty | AddressVerify |
|---|---|---|
| US deliverability and ZIP+4 | Yes, CASS certified | Yes |
| CASS certification for mail presort | Yes | No |
| International address validation | Yes, many countries | US residential focus |
| Address autocomplete | Yes | No |
| Rooftop geocoding | Yes | Coordinates where available |
| Residential vs non-residential | Not the focus | Yes |
| Property type classification | No | Yes, 7 classes |
| Estimated home value | No | Yes |
| Expanded property data (beds, baths, tax, listing) | No | Yes, same call |
| Real-time REST with JSON | Yes | Yes |
| Self-serve free tier | Yes, US lookups | 50 calls per month |
Why teams evaluate a Smarty alternative
You need residential property type, not just a valid address
A CASS-valid address can be an apartment, a business, or a PO box. AddressVerify classifies the property into seven residential types so you can route or reject a lead on the property itself, not just on whether mail is deliverable.
You want estimated home value in the same request
Smarty does not return a home value because that is not its job. AddressVerify returns an estimated value alongside validation, so you can score leads by buying power without stitching in a second property-data vendor.
You are qualifying leads, not presorting mail
Postal tooling optimizes for CASS compliance and mail streams. If your real workflow is "is this a homeowner worth a truck roll or a sales call," a property-aware API answers that question directly.
You want a self-serve free tier to test with production data
AddressVerify includes 50 API calls a month on the free plan with no credit card, so you can benchmark it against your own address list before you commit.
What the response looks like
A single POST returns validation and the residential property picture. Add ?expanded=true for beds, baths, lot size, tax, and listing history.
curl -X POST 'https://api.addressverify.io/service/lookup/address' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{"address": "1013 Bates Ave, Bakersfield, CA 93307"}'Returns:
{
"address": "1013 Bates Ave, Bakersfield, CA 93307",
"addressValid": true,
"homeType": "SINGLE_FAMILY",
"homeValue": 273900
}Full field list, authentication, and SDKs for JavaScript, Python, Go, and Rust are in the API documentation. See pricing for plan limits.
Where Smarty is still the right call
No tool wins everywhere. Here is where we would tell you to stay, or run both.
You send physical mail at scale
If you presort bulk mail and need CASS-certified standardization and DPV, Smarty is purpose-built for exactly that and AddressVerify is not a replacement for postal compliance.
You need international coverage
Smarty validates addresses across many countries. AddressVerify specializes in US residential addresses, so a global footprint is a reason to keep Smarty (or run both).
You need address autocomplete in a form
Smarty has a mature type-ahead autocomplete product. AddressVerify verifies and enriches a submitted address; it is not an autocomplete widget.
Smarty vs AddressVerify, answered
01Is AddressVerify a drop-in replacement for Smarty?
For US residential lead qualification, yes: you swap the endpoint and read a cleaner JSON response that also includes property type and estimated value. For CASS presort, international addresses, or autocomplete, Smarty remains the better fit and many teams run both, Smarty for the mail stream and AddressVerify for lead qualification.
02What does AddressVerify return that Smarty does not?
Residential property type (seven classes), an estimated home value, and an expanded property block with bedrooms, bathrooms, living area, lot size, year built, tax assessment, and listing history, all in the same request that validates the address.
03Is Smarty CASS certified and AddressVerify is not?
Correct. Smarty is CASS certified for USPS mail presort. AddressVerify focuses on residential property intelligence rather than postal certification. If CASS compliance is a hard requirement, keep a CASS-certified tool in that part of your pipeline.
04Can I try AddressVerify before switching?
Yes. The free plan includes 50 API calls a month with no credit card, and the free web tool on this site lets you check addresses immediately. Run your own list through both and compare the responses.
Compare it against your own data
50 free API calls, no credit card. Run your address list through AddressVerify and see the property data Smarty does not return.