The 843 area code traces coastal South Carolina — the Lowcountry and the Grand Strand — anchored by Charleston and principally serving Myrtle Beach, Hilton Head Island, and Florence. It was cut from the once-statewide 803 code in March 1998, and since October 2015 it has shared every inch of that territory with the 854 overlay, making the two codes interchangeable marks of the same coast.
Three codes divide South Carolina by geography, and 843 is the youngest of them. It is also the one that ran short of numbers first — a detail that says more about the modern coast than any tourism brochure. Here is the code’s story, from the 1998 split to a number supply now projected to hold into the 2050s.
A coastline gets its own code
By the mid-1990s the original 803 — South Carolina’s lone code since 1947 — needed relief for the second time in three years. The Upstate had already departed as 864 in December 1995. NANPA Planning Letter PL-086, issued September 5, 1997, announced the next cut: the Atlantic side of the state, defined as the Charleston and Florence LATAs plus South Carolina’s portions of the Savannah and Wilmington LATAs, would become the new 843. What remained of 803 — Columbia and the Midlands — is covered in our 803 area code guide.
The split went live at 12:01 a.m. Eastern on Sunday, March 22, 1998, with a six-month cushion: through September 27, 1998, a coastal call dialed with either 803 or 843 still completed, after which misdialed calls were routed to an intercept recording. PL-086 even published the plumbing — carriers could verify routing against test numbers at 843-667-0998 and 843-937-0998 before the cutover. Local calls stayed at seven digits, a habit the coast would keep for another seventeen years.
The youngest code ran short first
843’s oddity is speed. Measured from each code’s own start date in NANPA’s records, 803 ran 73 years before its overlay arrived — shedding territory twice along the way — and 864 lasted nearly 29. The coastal code needed help after seventeen and a half: on December 13, 2013, the South Carolina Public Service Commission approved an all-services overlay for 843 in Decision 2013-872, and NANPA introduced 854 in Planning Letter PL-463 (February 11, 2014), finalizing the rollout schedule in PL-474 that November.
The overlay followed the now-standard script. Permissive ten-digit dialing began March 14, 2015; mandatory ten-digit dialing arrived September 19, 2015; and the first 854 prefixes became eligible for activation on October 19, 2015 — the overlay’s official in-service date. A test number, (854) 854-1854, ran through the transition. Nobody’s 843 number changed; new lines simply began drawing from a second pool laid over the identical footprint.
That timeline handed the coast a distinction: the first mandatory ten-digit local dialing in South Carolina. Columbia followed when the 839 overlay went live on May 26, 2020, and the Upstate held out until 821 arrived over 864 on August 19, 2024. Every code in the state now belongs to an overlay pair — but the beach got there first, a fair proxy for where South Carolina’s growth in people, businesses, and phone lines had concentrated. Why regulators reach for overlays instead of another split is covered in our area code guide.
Dialing, 988, and a supply that reaches 2053
Local calls anywhere in 843 or 854 are dialed with all ten digits, toll calls with 1 plus ten — the plan NANPA published with the overlay and still lists for the pair. The early conversion also meant the coast could sit out the 988 scramble: when the national crisis line marched 82 seven-digit area codes onto ten-digit dialing in 2021, NANPA Planning Letter PL-556 listed no South Carolina code at all — the 843/854 coast was exempt for the simplest reason, having dialed ten digits since 2015.
Supply is equally undramatic. Per NANPA’s April 2026 NPA Exhaust Analysis, the 843/854 complex holds out to the first quarter of 2053 — fourteen quarters later than the previous forecast — and the July 6, 2026 delta revisions did not move the date. The pair carries no jeopardy status and no relief planning is underway. Barring a coastal boom beyond anything forecast, no third code is coming for decades.
Answered phones on a tourist coast
The 843 footprint runs on visitors and the businesses that serve them, and those businesses live or die by answered phones. A caller ID reading Charleston or Myrtle Beach instead of an out-of-state code is the cheapest trust signal available — the mechanics are laid out in our local-presence dialing guide. And because 854 is barely a decade old, prefix inventory across the pair remains plentiful: a business can still secure numbers in the exact rate centers its customers recognize.
One caveat cuts the other way: a coastal code on a screen proves nothing about the caller, because caller ID spoofing can paint 843 onto a call from anywhere. Looking local and being verifiably legitimate are separated at the carrier level — which is where we come in.
SIPNEX operates on FCC authority of its own — a direct authorization, not a reseller arrangement — and provisions local DID numbers in whichever coastal rate centers a campaign calls for, on the 843/854 coast or in any other US market. Those numbers reach your PBX or dialer over SIP trunking; each outbound call carries A-level attestation under our own STIR/SHAKEN certificate, and toll-free numbering comes from the same RespOrg-registered carrier.
The 843 area code FAQ
Which part of South Carolina does the 843 area code cover?
The coastal third of the state: Charleston and the Lowcountry down through Beaufort and Hilton Head Island, the Grand Strand around Myrtle Beach and Georgetown, and the Pee Dee region including Florence. NANPA defined the territory in 1997 as the Charleston and Florence LATAs plus South Carolina’s portions of the Savannah and Wilmington LATAs. The whole footprint is Eastern Time and has carried the 854 overlay since 2015.
Are 843 and 854 the same place?
Yes. 854 blankets the 843 region as an all-services overlay, approved by the South Carolina Public Service Commission in Decision 2013-872 and in service since October 19, 2015, per NANPA Planning Letter PL-474. It covers the identical coastal territory, so an 854 number on a business card or caller ID is exactly as local as an 843 one — newer lines simply draw from the younger pool.
When did 843 split from area code 803?
March 22, 1998, under NANPA Planning Letter PL-086 (September 5, 1997). The coast — Charleston, Myrtle Beach, Hilton Head, Florence — took the new 843 while Columbia and the Midlands kept 803. A permissive window let either code complete coastal calls until September 27, 1998, after which misdialed calls went to an intercept recording.
Do 843 numbers require ten-digit dialing?
Yes. Mandatory ten-digit local dialing took effect across 843 on September 19, 2015, ahead of the 854 overlay’s activation — the first such conversion in South Carolina, five years before Columbia and nine before the Upstate. Toll calls are dialed as 1 plus ten digits. Because the coast converted early, 843 and 854 had nothing to change when the 988 transition forced 82 codes onto ten-digit dialing in 2021 — no South Carolina code appeared on that list.
Is the 843 area code close to running out of numbers?
No. NANPA’s April 2026 exhaust study gives the 843/854 pair until the first quarter of 2053 — fourteen quarters more than the prior forecast — and the July 6, 2026 revisions passed it by. The complex holds no jeopardy status and no relief planning is in progress, so coastal number supply is comfortable for decades.
Whether the display should read Charleston, Myrtle Beach, or any other 843 rate center, SIPNEX provisions coastal South Carolina DIDs and delivers them over SIP trunking, with every call signed under our own STIR/SHAKEN certificate. Rates are posted, the desk answers at (833) 665-2220, and the contact page reaches the same people.
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