City Risk Report
Charleston, SC
Charleston County · Pop. 150,227
County-level composite · does not reflect parcel-specific conditions
Charleston buyers should weigh wind, flood, and residual-market costs as heavily as list price.
Editorial review: 2026-06-19 · Data retrieved: Jun 19, 2026 at 00:00 UTC (snapshot of historical values) · For the latest live data, run a lookup on the Snapshot tool.
Overall Risk Score
Top 5% most at-risk nationally
County-level composite · does not reflect parcel-specific conditions
Overall Risk
Top 5% most at-risk nationally
County-level composite · does not reflect parcel-specific conditions
Expected Annual Loss
Top 5% most at-risk nationally
Extreme · county composite
Est. Annual Insurance
$1,950 – $5,110
Directional range
Last Major Event
2015
South Carolina flood
Insurance Market Context
These scores are county-level composites derived from FEMA National Risk Index. Individual parcels may differ significantly. This is not a property appraisal.
Market Pressure
HIGH
South Carolina's admitted-carrier market is contracting. A broker with state-specific experience is strongly recommended.
Admitted Market Share
69%
Carriers exiting at 5.5% YoY in South Carolina.
Residual Market
$2,730–$7,154
annual · last-resort
FAIR Plan / Citizens exposure up 64% since 2020.
Premium Strain Index
Insurance is roughly 4.7% of median household income — well above the 2% middle-income affordability benchmark (First Street flags anything above 5% as financially unsustainable).
Premium-to-income ratio. Based on state Department of Insurance filings, average annual premiums in this area range from $1,950 to $5,110. Not an insurance quote. The First Street 12th National Risk Assessment characterizes any ZIP above 5% as financially unsustainable.
Charleston County Hazard Breakdown
Scores below are from the federal National Risk Index at the county level, refined with parcel-level signals where available (FEMA NFHL for flood, USDA WHP for wildfire, USGS PGA for earthquake, NWS for heat).
Top 5% most at-risk nationally
Hurricane
ExtremeTop 5% most at-risk nationally
Earthquake
ExtremeTop 17% most at-risk nationally
Extreme Heat
ExtremeTop 5% most at-risk nationally
Flood
ExtremeTop 10% most at-risk nationally
Wildfire
ExtremeData pending
Severe Storm / Tornado
Low riskLocal Flood Risk Cost Estimator
Flood insurance costs in Charleston, SC
In Charleston, SC, the directional annual NFIP flood insurance premium is approximately $2,205 (range $1,500–$3,500), and the estimated average historical flood claim in Charleston County is $80,600. Typical mapped exposure aligns with Zone A / AE (SFHA) (county flood percentile: 100).
- NFIP premium (mid)
- $2,205/yr
- Monthly escrow slice
- $125–$292/mo
- Avg. paid claim
- $80,600
- Lender may require
- Likely yes (SFHA)
Hurricane Windstorm Deductible Estimator
Named windstorm deductible exposure in Charleston, SC
In Charleston, SC, a 4% hurricane / windstorm deductible on a $450,000 insured dwelling implies roughly $18,000 out-of-pocket before the carrier pays (hurricane percentile: 100).
- Deductible %
- 4%
- Out-of-pocket
- $18,000
- Emergency fund target
- $27,000
Heat & HVAC Holding-Cost Estimator
Extreme heat carrying costs in Charleston, SC
In Charleston, SC, directional summer utility strain adds roughly $319/yr above a moderate-climate baseline (heat percentile: 83). Over 10 years, modeled hidden heat + HVAC costs land near $12,790 — about $1,279/yr to budget for cooling and accelerated equipment wear.
- Est. monthly electric
- $183/mo
- Annual heat tax
- $319/yr
- 10-yr hidden cost
- $12,790
Earthquake Insurance ROI Estimator
CEA-style earthquake coverage math in Charleston, SC
In Charleston, SC, directional earthquake coverage runs about $2,979/yr with a $112,500 deductible exposure (earthquake percentile: 99). Over 30 years, modeled premium spend is $89,370 vs. $25,309 illustrative expected loss.
Coverage may pencil — expected regional loss exceeds premium spend over 30 years.
- Est. annual premium
- $2,979/yr
- Deductible
- $112,500
- 30-yr premium vs loss
- $89,370 / $25,309
Wildfire & FAIR Plan Stress Test
Wildfire insurance non-renewal risk in Charleston, SC
In Charleston, SC, admitted-carrier withdrawal could push coverage through South Carolina Wind and Hail Underwriting Association at roughly $9,178/yr — about +$5,648/yr vs. a $3,530 baseline (wildfire percentile: 94).
Non-renewal risk: severe
- Baseline premium
- $3,530/yr
- Residual market est.
- $9,178/yr
- Annual uplift
- +$5,648/yr
What each hazard means for you
Expand any card to see the federal source citation and the buyer-specific action items our research team recommends for this hazard profile.
Hurricane Risk
Charleston ranks in the 100th national percentile for hurricane exposure in the FEMA National Risk Index.
FEMA · National Risk Index
Earthquake Risk
Charleston ranks in the 99th national percentile for earthquake exposure in the FEMA National Risk Index.
FEMA · National Risk Index
Extreme Heat
Charleston ranks in the 83th national percentile for heat exposure in the FEMA National Risk Index.
FEMA · National Risk Index
Flood Risk
Charleston ranks in the 100th national percentile for flood exposure in the FEMA National Risk Index.
FEMA · National Risk Index
Wildfire Risk
Charleston ranks in the 94th national percentile for wildfire exposure in the FEMA National Risk Index.
FEMA · National Risk Index
Severe Storm / Tornado
Charleston tornado data is unavailable. Run an address lookup for parcel-specific assessment.
FEMA · National Risk Index
FEMA Flood Zone
Is this specific parcel in a Special Flood Hazard Area?
The free address snapshot queries FEMA NFHL point-in-polygon and returns your exact FEMA Flood Zone (A, AE, X, etc.) in seconds.
Run a free address lookupCarrier Outlook
South Carolina's admitted-carrier market is contracting. A broker with state-specific experience is strongly recommended.
Data Sources
Data Sources & Methodology
FEMA— National Risk Index
Retrieved June 19, 2026
Editorial Analysis
Charleston, Charleston County has an overall National Risk Index score of 99 and an expected annual loss score of 100, placing it in the extreme national risk band. The dominant local perils are hurricane, flood, earthquake. The city-level scores below are county-level composites; actual parcel risk can differ meaningfully by neighborhood, elevation, and lot characteristics. Charleston's hurricane risk scores 100 at the 100th national percentile, placing it in the extreme band. This is among the highest exposure nationally; standard-market underwriting is increasingly selective and residual-market backup plans are worth modeling. Buyers should review wind mitigation reports, roof age, and storm-surge evacuation zone. Charleston's flood risk scores 100 at the 100th national percentile, placing it in the extreme band. This is among the highest exposure nationally; standard-market underwriting is increasingly selective and residual-market backup plans are worth modeling. Buyers should check FEMA flood zone status, elevation certificate, and drainage history. Charleston's earthquake risk scores 99 at the 99th national percentile, placing it in the extreme band. This is among the highest exposure nationally; standard-market underwriting is increasingly selective and residual-market backup plans are worth modeling. Buyers should verify seismic retrofit status and whether earthquake coverage is included. The South Carolina insurance market is currently under high pressure: admitted carriers write roughly 69% of new business and the residual market has grown roughly 64% since 2020. For higher-risk parcels in Charleston, the residual market can run from $2,200 to $4,700 annually. Directional standard-market premiums for the city typically range from $1,950 to $5,110, but parcel-specific factors can move quotes well outside that band. Buyers should use the address-level snapshot tool to pin these citywide averages to the specific property under consideration. A full L2 or L3 report will also surface flood zone status, insurance-market pressure, and action items tied to the exact parcel.
— Open Data Collective
Historical Events
South Carolina flood
Historic rainfall exposed severe urban flooding in the region.
Hurricane Hugo
Still the benchmark event for local wind and surge awareness.
ZIP Code Risk Profile
Representative ZIP Codes
29403
Charleston area
29406
Charleston area
29407
Charleston area
29412
Charleston area
29414
Charleston area
Risk varies significantly by ZIP code and parcel. Use the address-level report for precise, parcel-specific scores rather than city-wide averages.
NRI Score Components
County-level composite · does not reflect parcel-specific conditions
Charleston Climate Risk FAQ
Ready to check your specific address?
Considering buying in Charleston?
Two tiers, one funnel: run a free address lookup, then unlock the depth that fits your buying stage. Both options deliver a 12+ page climate brief before you go under contract.
Full Report
Tier L2
Address-level hazard and insurance feasibility snapshot — five hazards, 30-year projections, carrier pressure signals, and a buy / negotiate / walk-away read for pre-offer buyers. PDF delivered within 5 minutes.
- Five-hazard score breakdown: flood, wildfire, hurricane, earthquake, heat
- 30-year federal climate projections for heat, wildfire, and sea level rise
- Insurance premium estimate range based on state DOI filings
- Clear buy / negotiate / walk-away recommendation with plain-language reasoning
- Comparable lower-risk communities within 25 miles (up to 3 when available)
- Plain-English explanations of SFHA, BFE, residual market, and other insurance terms
- Single PDF you can share with your partner, agent, or inspector
Best for: pre-offer sanity check
Delivered: PDF by email within 5 minutes
Federal data: FEMA, USGS, NOAA, USDA, EPA
Delivered by email within 5 minutes of payment.
Pre-Purchase Audit
Tier L3
Under-contract diligence package: parcel flood zone verification, state insurance market analysis, NOAA claim history, and an evidence-backed negotiation brief to assess earnest-money risk. PDF delivered within 24 hours.
- Everything in the $19 Full Report
- Parcel-level FEMA flood zone verification (Zone A/AE/VE/X — point-in-polygon)
- State insurance market analysis: admitted carrier share, exit rate, residual market growth
- Premium Strain Index — insurance cost as % of local median income, with 2% / 5% affordability benchmarks
- 10-year NOAA Storm Events claim history for the ZIP code
- Negotiation leverage brief with specific, evidence-backed seller-concession asks (typically 3–5; fewer when data is limited)
- Total carrying cost estimate: HO-3 baseline + standalone perils + residual market fallback
- Identifies whether the property may become hard to insure before you close
- Gives you specific talking points for price, credits, and contingency negotiation
Best for: under-contract buyers
Delivered: PDF by email within 24 hours
Includes: 7-day no-questions-asked refund
Delivered by email within 24 hours of payment.