Facebook Ads Geofencing for Law Firms: What Is Actually Possible

You cannot draw a tight fence around a single building on Facebook. Meta location targeting has a roughly one-mile minimum radius and reaches people who live in or were recently in an area, not the phones sitting inside a specific address right now. I saw this question on r/AskMarketing: can you do geofencing on Facebook? It is a fair question, because the word gets used for two very different things, and the version most people picture does not exist on Meta.

What people mean by "Facebook geofencing"

When marketers say geofencing, they usually mean the tight version: draw a small digital boundary around one place, a stadium, a competitor's office, a hospital, and serve ads to the phones that physically cross into it, often for days afterward. That is real technology, but it is not what Facebook does. On Meta, "location targeting" is a much broader tool, and conflating the two leads to wasted budget and disappointed expectations.

What Facebook location targeting actually does

Meta lets you target a location three ways, and none of them is a tight fence:

• A pin plus a radius. You drop a point on the map and choose a radius, but the smallest radius Meta allows is about one mile (it varies by country and density). You cannot shrink it to a single building or block.
• Cities, regions, or postal codes. Useful for a metro or a service area, not for a specific address.
• A "who counts as here" setting. You choose people who *live* in the area, were *recently* in it, or are *traveling* in it. This is based on Meta's own location signals over time, not a live check of who is standing inside a polygon this minute.

So you can absolutely concentrate spend on a metro, a suburb, or a one-mile ring around your office. You cannot fence a courthouse door.

True geofencing needs a different tool

The building-level version runs on programmatic display and mobile ad platforms (DSPs), not Meta. They use device GPS to record which phones entered a drawn polygon, then retarget those devices with banner ads across apps and websites for a set window. It is a genuinely different channel with different inventory, different reporting, and a much higher tolerance for waste. If a vendor promises to "geofence" a location and run it "on Facebook," that is a red flag: they are either using loose radius targeting and calling it geofencing, or running display and mislabeling it.

The trap for law firms: geofencing ERs and hospitals

Here is where this stops being a media-buying question and becomes a bar-complaint question. The classic pitch to a personal injury firm is: geofence the emergency rooms and urgent cares, catch people the moment they are injured. Do not do it.

• In 2017 the Massachusetts Attorney General reached a first-of-its-kind settlement barring an ad firm from geofencing around hospitals and clinics to send ads to patients near or inside them, treating it as an unfair and deceptive privacy violation.
• Targeting people by their presence at a medical facility brushes against health-privacy expectations and, for lawyers, against attorney solicitation rules that restrict direct outreach to people known to need legal help because of a specific event.
• Even setting ethics aside, Meta cannot do the tight version anyway, so the only way to attempt it is the display channel that drew the enforcement action.

The credible move is the opposite of chasing the injured into the ER: be the firm they already recognize when they get home and start searching.

What to do instead

• Target the metro or a radius, then let intent do the qualifying. A one-mile ring around a neighborhood you serve is fine. Pair it with the awareness and retargeting job Meta is actually good at.
• Retarget your own visitors. The highest-return audience on Meta is people who already visited your site or engaged with your firm. That is consent-adjacent and effective, and it is where the budget belongs.
• Build authority so you are the recognized name. Meta reaches people before they search; Google catches them when they do. Treat social as the authority and demand layer, not a stakeout.

The takeaway

Facebook does not do true geofencing, and the tight version people imagine is a compliance minefield for law firms specifically. Use Meta for what it is good at, broad radius and metro targeting, retargeting your own audience, and authority content, and leave the ER stakeout alone. The firm that wins is the one people already trust when they finally reach for their phone.