FACTOR 01
Location (state and ZIP-level risk scoring)
The single largest factor. Florida runs 2.8x national; New Hampshire runs 0.44x.
Your state sets the base rate. Your ZIP then applies wind, hail, wildfire, and flood score adjustments. Insurify 2025 found premiums in high-wind ZIPs run roughly 58% above medium-wind ZIPs within the same state. A home 10 miles inland from the Gulf can pay half what an identical home on the coast pays.
FACTOR 02
Dwelling coverage amount
Approximately linear up to $500k, sub-linear above.
Coverage A is the single largest dollar input. Doubling Coverage A from $250k to $500k will roughly double premium. Above $500k the per-$1,000 rate drops by roughly 10% at each tier as carriers recognise that a $1M home is not twice as likely to burn down as a $500k home. At $1M replacement cost the per-$1k rate is typically around $6.60, versus $8.47 at $300k.
FACTOR 03
Roof age and material
An 11-to-15 year roof adds about $155/yr vs a <5 year roof. Roofs >20 years often forced onto ACV.
Roof age is the single biggest year-over-year inflator carriers have added since 2022. Insurify 2025 underwriting data shows the gap between sub-5yr and 11-to-15yr roofs widened from $49 in 2022 to $155 in 2025. Over 20 years, most carriers force the roof onto Actual Cash Value, depreciating a total-loss roof payout by 60% or more. Impact-resistant shingles (Class 4 rating) earn a 5-15% discount in hail-exposed states.
FACTOR 04
Home age and systems
A 1959 vs 2020 home with identical coverage can differ $1,000+/yr.
Older homes have older electrical (knob-and-tube, aluminium wiring), older plumbing (galvanised, polybutylene), and older HVAC. Each adds loss frequency. Homes built before 1960 without service updates typically attract surcharge or carrier refusal. Homes under 10 years old qualify for up to 25% new-home discount per ValuePenguin.
FACTOR 05
Construction type
Brick/masonry discount ~8% in wind zones. Manufactured/mobile +18%.
Frame construction is the industry default. Brick veneer and full masonry earn a modest discount in hurricane and tornado states because they resist wind better. Manufactured and mobile homes pay a surcharge and often require a specialty carrier (Foremost, American Modern). Log and post-and-beam construction can either discount or surcharge depending on carrier appetite.
FACTOR 06
Claims history (CLUE report)
One claim adds 10-20%; two in five years adds 30-50% or triggers non-renewal.
LexisNexis CLUE (Comprehensive Loss Underwriting Exchange) tracks all homeowner claims for seven years. Carriers pull this at quote time. One water or fire claim typically adds 10 to 20% on renewal. Two non-catastrophe claims in five years can add 30 to 50% or trigger non-renewal. Critically, a prior owner's claims on your property attach to the property, not the person, so you can inherit a loss history when you buy. Request a free CLUE report before closing on any home.
FACTOR 07
Credit-based insurance score
$2,000+/yr gap between excellent and poor credit. Banned in CA, HI, MA, MD.
Where permitted (46 states plus DC), carriers use a proprietary credit-based insurance score (not your FICO - LexisNexis and FICO both sell insurance-specific scores) as a behavioural predictor. Experian 2025 reports the premium gap between excellent (780+) and poor (sub-580) insurance scores can exceed $2,000 per year at identical coverage. Four states ban the practice outright: California, Hawaii, Massachusetts, Maryland. Washington temporarily banned during COVID and has since re-permitted with constraints.
FACTOR 08
Deductible choice (flat and percentage)
$1,000 to $2,500 saves ~9% on average.
Flat-dollar deductibles: raising from $1,000 to $2,500 saves approximately 9% per NerdWallet. Raising from $500 to $1,000 saves 5 to 10%. Percentage deductibles apply separately to wind, hurricane, named-storm, or hail losses in exposed states: a 2% of Coverage A deductible on a $400k dwelling equals $8,000 out of pocket on a hurricane claim, not $1,000. Some carriers quietly load a separate 1% roof deductible. See our deductibles page for the full picture.
FACTOR 09
Personal liability limit (Coverage E)
$100k to $500k adds typically under $50/yr.
Coverage E covers defence and damages when a guest is injured on your property or your household's actions cause off-premises harm. Default limits are often $100,000 or $300,000. Raising to $500,000 adds under $50 per year at most carriers and is almost always worth it for the incremental coverage. Above $500k, consider a separate personal umbrella policy (typically $150 to $300 per year for $1M in extra coverage).
FACTOR 10
Endorsements and riders
Water backup $50-$150, scheduled jewelry 1-2% of value, extended RC a few percent.
Endorsements are optional add-ons that close specific coverage gaps. Water backup / sump pump ($50 to $150/yr) covers sewer backup that standard HO-3 excludes. Service-line coverage ($30 to $50/yr) covers underground pipe and conduit failures. Equipment breakdown ($30 to $75/yr) covers HVAC and electrical component failures. Scheduled personal articles (1 to 2% of item value) removes sub-limits on jewellery, silverware, firearms. Extended replacement cost (5 to 10% premium increase) extends dwelling coverage by 25 to 50% if reconstruction exceeds Coverage A.
FACTOR 11
Insurer appetite and market conditions
Carrier exits force the last insurer to set the price.
Between 2023 and 2025, multiple national carriers restricted or exited specific states and ZIPs. State Farm paused new California business. Allstate restricted California and Louisiana. Farmers exited Florida for a period. AAA restricted Florida coastal. When choices narrow, the remaining carriers (often surplus-lines or state-run Citizens) set the price. This factor is invisible to any calculator, including ours - it shows up only when you actually request quotes and discover how few carriers will offer.
FAQ
Why did my home insurance go up so much at renewal?
Six common reasons, in order of frequency. First, construction cost inflation raising your reconstruction value. Second, weather losses in your region triggering a regional re-rate across the carrier's book. Third, your roof crossing an age threshold (5, 10, or 15 years). Fourth, a claim you filed (or even inquired about) in the last five years. Fifth, a carrier market exit forcing your policy onto a more expensive book. Sixth, a credit-based insurance score change (in states where it is used).
Does roof age really affect home insurance?
Yes, and the impact has grown. Insurify 2025 underwriting data shows a $155 per year gap between sub-5-year and 11-to-15-year roofs, up from $49 in 2022. Roofs older than 15 to 20 years are increasingly forced onto Actual Cash Value (depreciated settlement) rather than Replacement Cost, which can drop a total-loss roof claim from $20,000 to $6,000 in payout.
Does credit score affect home insurance rates?
In 46 states plus DC, yes. Four states ban credit-based insurance scoring for homeowner rating: California, Hawaii, Massachusetts, and Maryland. Where allowed, Experian 2025 data shows the gap between excellent and poor credit can exceed $2,000 per year at identical coverage. This is by far the single largest behavioural factor you control.
How much does one claim raise my premium?
Industry data from ValuePenguin and III shows one non-catastrophe claim typically raises your premium 10 to 20% at renewal. Two claims within five years often adds 30 to 50% and can trigger non-renewal at certain carriers. Weather-only catastrophe claims (hurricane, wildfire) usually impact less because they are coded as non-fault and tend to affect the entire regional book.