What is RDI, and where can I find it??

RDI stands for "residential delivery indicator". It tells you if a mailing address is a residential or business location.

The USPS keeps track of addresses that are registered specifically for commercial use, and they've set up their database so businesses with authorized programs and software can access that data.

You can use the Smarty single address validation tool to check if a single address is designated as residential or commercial.

(Need to check a lot of addresses? Try our US Street Address API. We return the RDI status of every address as part of the metadata set we return.)

In this article, we'll discuss the following topics:

Residential address vs. commercial address

Shipping can be a funny business sometimes. Mail carriers, be they private or otherwise, sometimes make decisions or take actions that seem...strange to the rest of us. The residential vs. commercial issue is one such topic.

Most private mail carriers charge one rate for shipping to a commercial address, and another for shipping to residential. The residential rates are typically higher.

Unfortunately, there is no way to intuitively determine if an address is a home or an office. So if you ship something to 221B Baker Street, expecting it to be a business address, you could be blindsided by an unexpected increase in fees if it is actually a residential address.

The reason is this: private carriers primarily service business locations. The vast majority of their work takes them to commercial and industrial districts of municipalities. While they do deliver to residential areas, it's often outside of their normal routes.

So if they're going to drive over the river and through the woods just to bring you cookies from your grandma's house, they're more likely to ask for a little something extra to compensate for it.

So how do you determine, in advance, if an address is a commercial or residential address?

That's where RDI comes in.

Residential delivery indicator (RDI)

Since the USPS organizes and manages the authoritative address database for the US, they already know if an address is residential or commercial. And the way that they share that data is through the Residential Delivery Indicator, or the RDI.

The Residential Delivery Indicator indicates whether or not the delivery address is residential. Pretty simple, right? So why would the USPS share this data with you? They have an ulterior motive.

Unlike the private carriers, the USPS doesn't charge different rates depending on whether or not an address is residential.

So, if you know that UPS and FedEx are going to charge you extra to ship something to an address, just because it's residential, you might prefer to go through the USPS instead. It's not a bad option, especially if your primary issue is the additional cost non-USPS couriers would charge you.

Private carrier 'residential' vs USPS 'residential'

The USPS isn't the only delivery service that knows if an address is residential or commercial. Private carriers also classify if an address is residential or commercial.

However, private carriers may classify an address as 'residential' that the USPS classifies as 'commercial'. Why?

When private carriers like UPS and FedEx classify locations as "commercial" or "residential," it's dependent largely on location, not the actual usage of the property.

Cities divide themselves up into different "zones," like residential, industrial, or commercial. These zones often restrict what can be built where, and overall they cause things to be built in their respective zones. Residential structures typically are built in residential zones, and commercial structures are built in commercial zones.

In other words, for private carriers, an address in a residential zone is a residential address, regardless of the structure's actual use. All other addresses are considered "commercial", and pay the lower rates.

That means that, according to the likes of UPS or FedEx, if your good buddy Greg chases his dream and builds a poodle salon in his home garage, that business is still classified by the zone it's in: residential. So, sending anything to him will require you to pay the higher rate when shipping via private carriers, even though you may be mailing something to his business, and not to his personal residence.

By contrast, the USPS RDI tells you what the use of a location is, rather than what zone it's in.

So, if your buddy Greg's poodle salon is a commercial use even though it's located in a residential zone, the USPS will tell you that your parcel will be going to a business location, even if the city has zoned the property as 'residential'.

How to use the USPS RDI

So how do you use the USPS RDI? The simplest way is to check an address with an address validation service like Smarty. We return the RDI as part of the metadata we return on every address.

If you're wanting to know where to find this fun little bit of information, here's what our output looks like on our single address validation tool:

RDI in live API output

And here it is again in the raw output from our US Street API:

RDI in raw output


The USPS Residential Delivery Indicator or RDI can tell you if an address is residential or commercial.

Need more clarification? Feel free to get in touch with us personally. We can shoot the breeze about our services, RDI, where to find RDI in our output, or even whether RDI is actually telling you what you want to know. We're happy to answer any of your questions, help you figure out which term to classify your address as, and ultimately get you into the right "zone." We're fully prepared to make the work of determining "residential" or "commercial" easier.