--- title: "South Carolina Trucking Email Security — 79.2% lack DMARC | EFROS" description: "Email-security posture of 4,191 active motor carriers in South Carolina. 79.2% of domains have no enforced DMARC, 8.2% use p=reject. Free, public, source-cited." canonical: https://efros.com/research/us-trucking-email-security-index/by-state/south-carolina/ --- - [Home](https://efros.com/) - /[Research](https://efros.com/research/) - /[US Trucking Email Security Index](https://efros.com/research/us-trucking-email-security-index/) - /[By State](https://efros.com/research/us-trucking-email-security-index/by-state/) - /South Carolina By State / South Carolina # South Carolina Trucking Email Security **79.2%** of active carrier domains in South Carolina have no enforced DMARC. That leaves freight operators open to email impersonation, payment-redirect fraud, and cargo theft via phishing. Edition: 2026-Q2 State rank: #30 Carriers: 4,191 Domains: 3,577 By [Stefan Efros](https://www.linkedin.com/in/stefanefros-cyberdefense/), CEO & Founder, EFROS Updated · May 19, 2026 No enforced DMARC 79.2% national: 80.1% p=reject 8.2% national: 7.5% Microsoft 365 37.3% national: 38.1% M365 + no DMARC (carriers) 967 national: 92,822 MTA-STS 3.6% national: 3.3% DNSSEC 7.5% national: 6.1% Dead domains 242 of 3,577 scanned Total carriers 4,191 245 with dead domain ## Risk bands — South Carolina carriers Carrier counts by risk band (composite email-security pain score). Critical = score 70+; Minimal = score <15. | Risk band | Score range | Carriers | Domains | | --- | --- | --- | --- | | Critical | score 70+ | 311 | 290 | | High | score 50–69 | 1,232 | 1,045 | | Medium | score 30–49 | 1,756 | 1,438 | | Low | score 15–29 | 618 | 537 | | Minimal | score ## South Carolina vs. national average No enforced DMARC 79.2% vs 80.1% national p=reject adoption 8.2% vs 7.5% national MTA-STS 3.6% vs 3.3% national DNSSEC 7.5% vs 6.1% national ## What the South Carolina numbers actually mean **DMARC posture.** South Carolina's share of carrier domains with no enforced DMARC sits at **79.2%**, within 0.9 points of the national average. enforced p=reject DMARC adoption is roughly in line with the national pool: most South Carolina domains either have no DMARC at all or are stuck at the monitor-only p=none policy. At the protective end of the distribution, 8.2% of South Carolina domains are at p=reject, the only DMARC policy that actually instructs receivers to drop spoofed mail. **Microsoft 365 surface.** Microsoft 365 mailflow adoption tracks the national distribution closely, so the 967 M365 carriers in South Carolina with DMARC disabled represent the same "paid-for-but-switched-off" pattern that drives the national headline. That share is **23.1%** of all South Carolina carriers — a one-flag-flip remediation set that any regional MSP or in-house IT lead can clear in a single quarter. **Transport encryption.** MTA-STS adoption sits at 3.6%, materially below the threshold a freight payment-redirect attacker would have to clear to be inconvenienced by transport-layer policy. DNSSEC adoption in South Carolina runs at **7.5%** (vs 6.1% national), which matters for downstream DKIM and MTA-STS validation but is still a minority signal. **Risk-band shape.** South Carolina's critical-band share is 7.4% versus 8.4% nationally, with the pressure shifting into the high band (29.4% of state carriers) where one or two control gaps still leave room for impersonation. The composite pain score blends SPF posture, DMARC enforcement, MTA-STS presence, and DNSSEC, so a carrier clusters in the critical band only when several controls fail together. Remediation that flips DMARC to enforcement plus turns on MTA-STS typically moves a carrier two bands down in one quarter. **What this means for buyers and shippers.** If you are dispatching freight, settling broker payments, or receiving rate confirmations from South Carolina-based carriers, the operational exposure is the 79.2%of domains that cannot stop a stranger from sending email in the carrier's name. Payment-redirect and load-redirect fraud rides on exactly that gap. Verifying a counterparty's DMARC posture before a first wire (a 30-second DNS lookup) is the cheapest control in the freight stack. ## Compare South Carolina with other states States closest in carrier-count rank to South Carolina. Each is scored on the same DNS-derived control set, so the comparison is apples-to-apples. [### Kansas Rank #2975.6% no DMARC · 4,768 carriers](https://efros.com/research/us-trucking-email-security-index/by-state/kansas/) [### Connecticut Rank #3179.2% no DMARC · 4,450 carriers](https://efros.com/research/us-trucking-email-security-index/by-state/connecticut/) [### Virginia Rank #2876.2% no DMARC · 5,112 carriers](https://efros.com/research/us-trucking-email-security-index/by-state/virginia/) [### Nebraska Rank #3276.7% no DMARC · 4,402 carriers](https://efros.com/research/us-trucking-email-security-index/by-state/nebraska/) [### Tennessee Rank #2775.9% no DMARC · 5,568 carriers](https://efros.com/research/us-trucking-email-security-index/by-state/tennessee/) [← Full US Trucking Email Security Index](https://efros.com/research/us-trucking-email-security-index/) [← All states](https://efros.com/research/us-trucking-email-security-index/by-state/) [Switch to cargo-segment view →](https://efros.com/research/us-trucking-email-security-index/by-cargo/) ## See where your own domain stands The research is free and self-serve. Run the same public checks on your own domain in about a minute — SPF, DKIM, DMARC, MTA-STS, DNSSEC, and more — and get a scored report by email. No agents, no credentials. [Scan your domain free →](https://efros.com/tools/security-scan/) [Email security for fleets](https://efros.com/industries/trucking-company-msp/) [Talk to EFROS](https://efros.com/contact/?source=trucking-email-research) Data as of 2026-05-20from public DNS measurements. Statistics are domain-weighted unless noted. State scope is the carrier's FMCSA-registered state. Methodology: [read the full index](https://efros.com/research/us-trucking-email-security-index/).