What is eLOT®?

The simple definition of eLOT® is that it’s a mail sorting product developed by the United States Postal Service (USPS). It stands for Enhanced Line of Travel, and gives mailers the ability to sort their mailings in approximate carrier-casing sequence.

What Does That Mean?

Insert meme of confused minion here, right? For anyone who isn’t fluent in mail-talk, that basically means that eLOT® is a product that helps to presort your mail, improving delivery accuracy and increasing mailing rate discounts. eLOT® takes the guesswork out of mail delivery by using a sequence of numbers and codes to indicate exact mailing addresses.

I’m a USPS eLOT® Pro

If you’re already fluent in the mail-bending ways of the USPS, that’s great! We’ve got more details for you. eLOT® has a sequence number field and an ascending or descending code. The sequence number indicates the first delivery occurrence made within a carrier route. The ascending or descending code indicates the delivery order within the sequence number.

The History of eLOT®

Don’t worry, we promise this won’t be as boring as it was in high school — but it will be just as educational! eLOT® is not an entirely new product, but rather an expansion of an existing USPS product: Line of Travel (LOT®).

LOT® and eLOT®: What’s the Difference?

LOT® narrows down a mail carrier’s delivery route to the block face level (i.e., the Zip+4 code) and identifies whether an address is on the odd or even side of a street.

eLOT® narrows down this route even further by identifying the address at a delivery point level (i.e., the house number).

Ready to start using eLOT®?

Businesses benefit from using a postal address verification service and eLOT® in a variety of ways.

Increases ROI

Reach customers the first time and improve your mail campaign results.

Reduces Fraud

Identify invalid or fake addresses before you send mail and packages.

Improves Data

Keep your contact lists up to date and your data accurate 24/7.

Saves Time

Standardize and validate bulk addresses in a fraction of a second.

Simplifies Mailing

Never worry about undeliverable mail or postal returns again.

Includes Discounts

Qualify for additional barcoding, presorting, and discounts.

If you want to make sure your mail and packages are delivered quickly to the correct address, then use an address verification system and eLOT® prior to sending them. Simply run bulk addresses through an address API and get results in a fraction of a second. eLOT® is perfect for…

First Class Mail


Standard Mail

Esendex’s PAV API returns the following information at no additional charge:

The address has correct primary and secondary data

The address has correct primary but not secondary data

The address cannot be validated; data is likely incorrect

Examples of eLOT®

Esendex’s PAV API includes eLOT® data as part of its address verification solution.

Sample File Data














Want to view an eLOT® sample data file in its entirety? Click here.

Want to view the eLOT® Master Product file format? Click here.

In order to use eLOT®, USPS requires address lists to be processed by a CASS Certified address verification service such as Esendex’s Postal Address Verification (PAV) API. Address verification services run mailing data through the data hygiene process, which means that they check and correct bulk addresses to meet USPS standards.

About Esendex’s PAV API

Our Postal Address Verification (PAV) API saves time, money, and resources by verifying addresses for deliverability before mail and packages are sent out. PAV uses a simple three-step process to ensure your postal addresses are accurate.

1. Standardize

Standardization formats addresses to meet USPS standards. Want to learn more about standardization? We’ve got you covered.

2. Correct

Correction identifies and corrects wrong address information. But standardization and correction sound similar… what’s the difference? Read about it here.

3. Validate

Validation uses the USPS databases to ensure address deliverability. Validation, verification, valedictorian? We can help with at least two of those.

What Does Esendex’s PAV API Do?

We help you save time, money, and resources by correcting addresses for deliverability before mail and packages are sent out. PAV API helps businesses ensure data quality for all U.S. customers.

Keep in Mind…

Address correction greatly increases delivery time and the likelihood of a successful delivery. However, correction alone does not guarantee deliverability or validity, which is why our PAV API also includes address verification and address standardization.

  • Corrects spelling errors
  • Formats with USPS capitalization
  • Fixes incorrect abbreviations
  • Formats ZIP Codes to ZIP+4
  • Identifies missing information
1. What is eLOT®?

eLOT® is a USPS product that helps presort mail and increase delivery accuracy and efficiency by sorting mailings via an approximate carrier-casing sequence.

2. How do I use eLOT®?

To use eLOT®, simply sign up for a CASS Certified address verification service. Address verification services like Esendex’s PAV API include eLOT® data.

3. What is CASS Certification?

For an address verification software to gain CASS Certification, it must have high accuracy scores for ZIP+4, carrier route, LACSLink®, delivery coding, DPV®, and RDI.

4. How does eLOT® benefit my business?

Using eLOT® and an address verification service increases your ROI, reduces costs, saves time and money, and improves data management and overall data quality.

5. Why should I use Esendex’s PAV API?

PAV is an all-in-one API solution for all of your bulk address verification needs. It’s fast, affordable, and effective for every business across any industry. Check out our PAV API Home page to learn more about our product and how Esendex can help you.

6. What if I need help?

General customer and technical support is available during business hours, and emergency support is available 24/7. Please see our Contact page for more information.

7. Still have questions?

Read our full list of general and technical FAQs.

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Let’s start sending, together.