How 811 Works — From Ticket to Dig

Why 811 Was Created

Before 811 existed, each utility company had its own notification number. A homeowner planning to install a fence might need to call five or six different numbers — gas, electric, water, cable, phone — and hope they had the right numbers for their area. Misses were common and costly.

In 2005, the FCC designated 811 as a single national three-digit number that routes to the correct regional one-call center based on the caller's location. Each one-call center is a clearinghouse — when you call or submit a ticket online, they notify every member utility company that has infrastructure in your area. Utilities then have a legally mandated window to respond.

The system is funded by the utility companies themselves, which is why the service is free to callers and ticket submitters.

The 6-Step 811 Process

1. Pre-mark your excavation area in white

   Before you call or submit a ticket, use white spray paint, white flags, or white chalk to mark the outline of where you intend to dig. This is your "pre-mark" — it tells the incoming locators exactly where to focus. On a fence job, mark each post location. On a larger project, outline the full dig zone. Pre-marking dramatically improves locate accuracy. Some states require it for commercial projects; it's highly recommended for any job.

2. Call 811 or submit a ticket online

   Dial 811 from any phone — it routes to your regional one-call center automatically. Or use your state's online portal (most states now have them — see the State Info tool). You'll provide: your name and contact info, the excavation address, the type of work (fence, landscaping, pool, etc.), the planned start date, and the size of the dig area. You'll receive a confirmation number — save it.

3. One-call center notifies all member utilities

   Within minutes of your ticket being submitted, the one-call center electronically notifies every utility company that has registered infrastructure in or near your dig area. This typically includes your electric provider, natural gas company, water and sewer authority, telephone company, and cable TV/internet provider. Each company receives the ticket details and your pre-marked area coordinates.

4. Utility locators visit and mark the area

   Each utility that receives a notification sends a locator — either an employee or a contracted locate service — to your property. The locator uses electromagnetic equipment to detect buried metallic lines and paint or flag their location on the surface using APWA color-coded markings. Lines that run through your dig area are marked with their centerline path. Lines with no conflict are marked "clear" in the ticket system.

5. Wait the full required period and verify all responses

   You cannot dig until: (a) the required waiting period has elapsed — 2–3 business days depending on your state — AND (b) every utility has responded to the ticket. Check your ticket status online using your confirmation number. Do not assume that because some utilities have marked, all have. If a utility hasn't responded by the deadline, contact your one-call center before digging.

6. Dig carefully, respecting tolerance zones

   Once all utilities have responded and the wait period has passed, you may begin excavation. Any marked utility lines require a "tolerance zone" — typically 18–24 inches on each side of the mark — where only hand digging is permitted. Outside the tolerance zone, mechanical equipment may be used. Dig slowly near marks, exposing each utility line before going deeper.

How to Read Your Ticket Status

Every one-call center provides a way to check whether utilities have responded to your ticket. Using your confirmation number, you can typically see each utility's status:

What Happens After the Marks Are Down

Once marks are in your yard, treat them as the map to what's below. A few important rules:

• Don't remove flags before work is complete. Flags mark the line path. Once they're gone, you're digging blind.
• Photograph all marks before digging begins. If marks are disturbed by rain, wind, or foot traffic, you have a record. Photos also protect you legally if a dispute arises about whether lines were properly marked.
• The mark shows approximate centerline, not exact depth. Always call the utility if you need depth information for specific post or pier locations.
• Hand dig the full tolerance zone. This means 18–24 inches on each side of any colored mark. No mechanical equipment in this zone regardless of depth.
• Expose utilities before going deeper. Once you've exposed a utility line by hand digging, you can see exactly where it is before committing to deeper work nearby.

The One Thing 811 Cannot Do

811 only marks infrastructure owned by member utility companies. Your irrigation system, landscape lighting, invisible dog fence, private propane line, outbuilding power — none of these appear in the 811 system. Millions of homeowners have private underground infrastructure they installed (or that was installed when they bought the house) that has no registration in any database.

After your 811 locate is complete, you still need to assess and locate any private lines in your dig area. See the complete guide: What 811 Does NOT Mark.

Online vs. Phone: Which Should You Use?

Both work. Online submission is available in most states and has some practical advantages: you can be more precise about location (using a map interface), you get written confirmation immediately, and you can track ticket status in real time without calling. Phone calls work fine too — and in some rural areas or states with less developed online systems, a phone call may get faster human handling.

For complex projects with unusual footprints, large dig areas, or locations that are hard to describe verbally, the online map-based submission is usually more accurate. For simple residential jobs — fence posts, a deck, a single-tree removal — either method works equally well.

Frequently Asked Questions

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