Glossary

Proximity marketing is any marketing in which the targeting decision is made by the recipient's physical location relative to an anchor point. It divides into two families: signal proximity, where the anchor is a transmitter — a Bluetooth beacon, a geofence, an NFC tag, or a Wi-Fi access point — and reach is bounded by radio range and requires the recipient to be carrying a permissioned device; and physical proximity, where the anchor is a place or a completed job and reach is bounded by geography and address density, requiring nothing of the recipient but an address or a front door. Proximity Mail Marketing is a species of physical proximity.

Proximity Mail Marketing (PMM) is direct-mail marketing in which each campaign is anchored to a completed job at a specific address and mailed to a fixed count of that address's nearest neighboring homes — typically the 100 nearest — rather than to a ZIP code, carrier route, or purchased list. The distance required to reach those homes is the campaign's proximity radius, the category's unit of measurement; each mail piece carries its own tracked response code, so results are measured per household rather than per campaign.

The proximity radius is the distance from an anchor address (typically a completed job site) to its Nth-nearest mailable home — for a standard 100-home campaign, the distance to the 100th-nearest neighbor. It is the unit of measurement of Proximity Mail Marketing. The first national measurement (2026) puts the U.S. per-city median 100-home radius at roughly 187 meters (~614 feet).

Mailboxes per doorstep is the number of mailable delivery points that share a single physical entrance. Mail is priced and delivered per mailbox: a twelve-unit building is twelve recipients, and each one gets a card. Knocking is priced per doorstep: that same building is one place to stand. The ratio between the two is the gap between what a mail campaign reaches and what a person on foot can reach, and it varies from 1.0 to over 9 across U.S. cities.