Short answer: South Carolina's beachfront management law (SC Code 48-39-250 through 48-39-360) has the SC Department of Environmental Services' coastal management staff draw two lines along every developed ocean beach. The baseline is generally the crest of the primary oceanfront sand dune; the setback line sits landward of it by 40 times the average annual erosion rate, and at least 20 feet. New lines for Hilton Head Island took effect July 24, 2026. Between the lines, a new home is capped at 5,000 square feet of heated space and must sit as far landward as practicable, and a sale contract for property seaward of the setback line must include a disclosure statement (48-39-330).

Key facts

  • The law: SC Code 48-39-250 through 48-39-360, first enacted in 1988 (Act No. 634) and reformed in 2018 (Act No. 173, the Beachfront Management Reform Act).
  • The agency: SC Department of Environmental Services (SCDES), Bureau of Coastal Management. The Code calls it the Division of Coastal Management and, since May 15, 2026, no longer names DHEC.
  • Baseline: generally the crest of the primary oceanfront sand dune (48-39-280(A)(1)).
  • Setback line: landward of the baseline by 40 times the average annual erosion rate, never less than 20 feet (48-39-280(B)).
  • Hilton Head's current lines: established in Phase I of the 2024 to 2028 review and in effect as of July 24, 2026 (SCDES).
  • Challenging a line: a review request by certified mail within one year of the line's establishment, $100 per property (48-39-280(F)).
  • Between the lines: new homes up to 5,000 square feet of heated space, as far landward as practicable, nothing on the primary dune (48-39-290(B)).
  • Seaward of the baseline: no new construction except listed items such as walkways up to 6 feet wide and wooden decks up to 144 square feet, with a permit (48-39-290(A)).
  • Contract disclosure: required for property wholly or partly seaward of the setback line (48-39-330).

What are the baseline and the setback line?

They're two lines the state draws parallel to the beach. SCDES puts it simply: the baseline is the more seaward line, and the setback line is the more landward one. The setback line marks the landward edge of the state's direct permitting authority over the beach and dune system.

Where the baseline goes depends on the type of shoreline (48-39-280(A)):

  • Standard erosion zones, most of an island's ocean beach: at the crest of the primary oceanfront sand dune. If the dune is more than 200 feet behind the vegetation line, or there's no dune, or the shore has been altered by seawalls, the law gives rules for placing it.
  • Inlet zones that aren't stabilized by jetties or groins, such as beaches next to a sound: at the most landward point of erosion at any time in the past 40 years, unless the data show the shore is unlikely to return there.

The setback line is then drawn landward of the baseline at 40 times the average annual erosion rate, and at least 20 feet (48-39-280(B)). A beach that's eroding fast gets a setback line far behind the dune. A stable or growing beach gets the 20-foot minimum. Since the 2018 reform, a baseline can't move seaward of the most seaward of its 2008 to 2012 position and the positions SCDES proposed on October 6, 2017 (48-39-280(A)(4)). Beach renourishment doesn't push the lines out toward the ocean.

Did the lines on Hilton Head change in 2026?

Yes. The law requires new lines every seven to ten years (48-39-280(C)). SCDES is running the current review in phases from 2024 to 2028. Hilton Head Island was in Phase I, with Daufuskie, Bay Point, St. Phillips, Pritchards, Fripp, Hunting, Harbor and Little Capers islands. SCDES says those lines were established and in effect as of July 24, 2026.

Two things follow for buyers. First, any survey, line report or listing note made before July 24, 2026 may show the old lines, which dated from 2018. Ask for the current ones. Second, a landowner who believes a new line hurts their property has one year from the date the line was established to ask for a review, by certified mail to the Bureau of Coastal Management with a $100 fee per property. A contested case can then go to the Administrative Law Court within 30 days of the final agency decision (48-39-280(F)). If you're buying an oceanfront lot, ask the seller whether they filed a review.

Many older articles still name DHEC or its Office of Ocean and Coastal Resource Management as the agency. Coastal management moved to the new Department of Environmental Services, and 2026 Act No. 146 updated the Code's wording to match.

What can you build between the baseline and the setback line?

Less than you can landward of it. Under 48-39-290(B):

  • New homes can extend seaward of the setback line only if the owner certifies to SCDES that the home is no larger than 5,000 square feet of heated space, sits as far landward on the lot as practicable, isn't built on the primary dune or seaward of the baseline, and doesn't have a seawall or other erosion control device built into it. The owner submits a drawing showing the footprint and the lines.
  • Additions are allowed if the home and the addition together stay at or under 5,000 square feet of heated space.
  • Repairs of homes damaged but not destroyed beyond repair are allowed, and normal maintenance needs no notice.
  • Pools: no new pool seaward of the setback line unless it's behind an erosion control structure that already existed or was permitted, and as far landward as practical.
  • Seawalls, bulkheads and revetments: no new ones seaward of the setback line, with narrow exceptions. An existing one destroyed more than 50% above grade can't be repaired or replaced, and must be removed at the owner's expense.
  • Dune vegetation: destroying beach or dune plants seaward of the setback line is prohibited unless there's no feasible alternative, and then replanting is required (48-39-310).

Anything else between the lines needs an SCDES permit (48-39-290(B)(4)). Seaward of the baseline, only listed items are allowed, such as wooden walkways up to 6 feet wide, wooden decks up to 144 square feet, dune fencing and replanting, most of them with a permit.

Can you rebuild after a hurricane?

Usually, with conditions. The state measures "destroyed beyond repair" as more than 66 and two-thirds percent of the replacement value of the home (48-39-270(11)). A home damaged less than that can be repaired. A home destroyed beyond repair by natural causes can be replaced after the owner notifies SCDES that the new home has no more square footage seaward of the setback line than the old one, is no wider along the coast, is no farther seaward, is moved landward of the setback line where possible, and isn't seaward of the baseline (48-39-290(B)(1)(b)(iv)).

Don't confuse this with the Town's flood rule. The Town of Hilton Head Island treats a building as substantially damaged when repairs cost 49% or more of its market value, and then the whole building has to meet current flood standards. On an oceanfront lot both rules can apply at once, and the Town's threshold is lower. See the 49% rule.

What does the seller have to disclose?

A setback statement in the contract. SC Code 48-39-330 says a contract of sale or transfer of property located wholly or partly seaward of the setback line or the jurisdictional line "must contain a disclosure statement" that the property is or may be affected by the setback line, the baseline and the seaward corners of all habitable structures, referenced to the South Carolina State Plane Coordinate System (NAD 1983), and the local erosion rate most recently published by the department for that zone. Language "reasonably calculated to call attention to" those items complies.

The section is "regulatory in nature," so a contract without the statement is still legal and enforceable. That puts the burden on you. This statement is separate from the state's residential property condition disclosure, which separately asks about erosion, erosion control structures and beach renourishment assessments. See the SC property disclosure statement.

How do you find the lines on a specific lot?

Start with SCDES's Beachfront Jurisdictional Lines Viewer at gis.des.sc.gov/shoreline. It shows approximate line locations, line reports, erosion rates and downloadable coordinates. SCDES says the map is approximate and the exact position on a property needs a property-specific survey. For questions, the Bureau of Coastal Management's number is 843-953-0200.

The Town has its own rules too. On the beachside of a beachfront lot, removing trees needs a Town permit, and if the home is in flood zone VE, the Town requires the lowest supporting member to be at least 3 feet above base flood elevation or 13 feet above mean sea level, whichever is higher. See Is Hilton Head in a flood zone?

How we help

On any oceanfront or second-row listing we'll pull the current SCDES line report and erosion rate, ask for the seller's survey showing the lines, request the elevation certificate and flood zone, and make sure the setback disclosure is in your contract. For a lot you plan to build on, we'll recommend you hire a surveyor before you're bound.

Questions

Does the setback line affect oceanfront villas and condos?

Yes, if the building sits wholly or partly seaward of the setback line. The law treats each condominium building as a separate habitable structure, so the rebuild rules apply to the building, not your unit alone. Ask the association for its line information and any storm rebuild plan.

Does beach renourishment move the setback line?

No. Since the 2018 reform, a baseline can't move seaward of its 2008 to 2012 position or the positions proposed in October 2017, so added sand doesn't let you build closer to the ocean. The current seller disclosure form asks separately about beach renourishment assessments.

Do second-row homes need to worry about the setback line?

Usually not, but check. On a fast-eroding stretch the setback line can sit well behind the dune. The SCDES viewer shows where the line falls, and a survey confirms it.

Sources

  1. SC Code Title 48 Chapter 39 (48-39-250 through 48-39-360, beachfront management), SC Legislature (checked October 2026)
  2. State beachfront jurisdictional lines, SC Department of Environmental Services (checked October 2026)
  3. SC beachfront jurisdictional lines viewer, SC Department of Environmental Services (checked October 2026)
  4. Substantial improvement and damage, Town of Hilton Head Island (checked October 2026)
  5. Build responsibly, Town of Hilton Head Island (checked October 2026)