What is geofencing advertising? A plain-English briefing.

Draw a line around a building. Every phone that crosses it can see your ads for weeks afterward. That is the whole trick — and it is more accessible than you think.

Geofencing is location-based advertising at its most literal. You define a boundary on a map — a competitor's storefront, a trade show floor, a neighborhood — and devices that physically enter that boundary become an audience you can serve ads to, both while they're inside it and after they leave.

How it actually works

1. Draw the fence. Any address, building, event venue or area, block by block.
2. Capture the audience. Devices that enter the fence are added anonymously to your audience pool.
3. Serve the ads. Your display ads follow those devices across the apps and sites they use afterward.
4. Measure walk-ins. Conversion zones let you count devices that later showed up at your location.

Four fences worth drawing

• Your competitors' storefronts. Their foot traffic is, by definition, people who buy what you sell.
• Trade shows & industry events. A few days of fencing captures a year's worth of qualified prospects.
• Your own service area. Stay in front of the neighborhoods you already serve.
• Past-customer neighborhoods. Reactivation without buying a list.

Why you don't see it sold off the shelf

Programmatic geofencing typically moves through agency partners with campaign minimums — it's sold as a managed service, priced accordingly. That's why most small businesses have heard of it and never run it. Through Digital Assault AI it's included in the arsenal at wholesale, so the math works at small-business scale: you can fence a single competitor location and see whether it pays before you go wider.