Postal Address Verification API

Access detailed, accurate, and real-time USPS address verification data to ensure delivery to recipients, saving your business time and money on returned or unsuccessful deliveries.

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USPS Address Verification API Features

Our address verification API has the tools you need to efficiently deliver mail directly to recipients and reduce time and money wasted on unsuccessful deliveries.

Address Standardization

Automatically update addresses to adhere to the United States Postal Service’s (USPS) formatting. This ensures successful deliveries.

Address Correction

Automatically correct any errors in shipping addresses before packages are sent to recipients to save money & stop undeliverable mail.

Address Validation

Compare each customer address with the USPS database & find a match. If a match is found, then that address is deliverable.

Residential Delivery Indicator

USPS RDI, or Residential Delivery Indicator, identifies whether a U.S. address is classified as residential or business.

Carrier Route

Carrier route codes can be presorted to take advantage of presorting postage discounts.


Ensure correct primary & secondary data, so mailers can sort their packages in approximate carrier-casing sequence – reducing your costs and boosting ROI.

Legislative Data

Return legislative information, including the congressional district number along with the senate & house district of the address.

Proper Case Formatting

Get data in Proper Case format rather than the default uppercase format, so bar codes can be automatically scanned.

“We have used PAV API for over 30 years. Since switching to Esendex we have noticed increased accuracy at a fraction of the cost of other available services. I haven’t found anything we don’t like about PAV API.


Why Choose Esendex’s USPS Address Verification API?

A trustworthy address verification service is crucial if you collect Canadian and US postal address data through a sales or enrollment portal, and Esendex’s PAV is fast, reliable, and delivers results in a fraction of a second.

1. World Class Support

We understand that most address verification service providers don’t have active online support channels you can speak to when you need it the most, which is why our emergency support is available 24/7. You can expect fast response times and fast resolution via email, chat, or phone.

2. Automated Verification, Correction, and Standardization

Our address verification API allows you to upload a list of addresses, so they can automatically be adjusted to standard formatting, corrected for spelling errors, and validated as a deliverable address – saving you time, money, and resources wasted on unsuccessful deliveries.

3. Government Level Security

Our API for address verification is 256 Bit Encrypted (typically only reserved for governments and militaries), SOC2 Type 2 Certified, and HITRUST Certified.

Hardware-based verification servers are strategically located throughout the US-owned and operated by Esendex.

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How USPS Address Verification Works

Our USPS address verification API is perfect for companies looking to correct, standardize, and verify mailing addresses while decreasing unsuccessful deliveries. No matter if it’s residential or business addresses, you’ve retain control with Esendex’s address verification API.

ROI, Cost, & Data Management

Reach customers the first time and improve ROI on mail campaigns by reducing costs from undeliverable mail and returns, and qualifying for bulk discounts. Standardize, verify, and correct your address data to maintain a clean database at all times.

Address Verification Plans

We offer an affordable, unlimited USPS address verification plan that won’t limit you by usage, transactions, or time commitment. Our transparent pricing ensures there are no hidden fees, and offers you the option of paying per-transaction for ease of use.

Let’s start sending, together.