Flood Insurance Calculator

The coverage gap most homeowners don’t know about

Flooding is the most common and costly natural disaster in the United States, yet it’s specifically excluded from standard home and renters policies. That surprises people after the fact — they assume “water damage” is covered, but the policy distinction is sharp: a burst pipe inside the home may be covered, while rising water, storm surge or rainfall runoff entering the home is not. Closing that gap requires a dedicated flood policy, and sizing it correctly is what the calculator above is for.

Building vs. contents — two separate coverages

Flood policies split protection into two parts you buy separately:

• Building coverage protects the structure itself — foundation, walls, electrical and plumbing systems, furnace, water heater, built-in appliances and permanently installed fixtures. Size it to your rebuild value, just like your home insurance dwelling figure.
• Contents coverage protects your belongings — furniture, electronics, clothing and other personal property. Renters can buy this on its own, since the landlord insures the structure.

The calculator estimates both and compares them with the NFIP caps so you can see whether the program alone is enough or whether you need to top up.

NFIP limits and what to do above them

The National Flood Insurance Program caps residential coverage at $250,000 for the building and $100,000 for contents. If your home’s rebuild value or your contents exceed those amounts, the gap doesn’t have to go uninsured — a growing market of private excess-flood insurers will cover values above the NFIP caps. The calculator flags this “above caps” figure so you know exactly how much excess coverage to ask about.

A worked example

Imagine a home with a $300,000 rebuild value and $75,000 of contents. The NFIP would cover $250,000 of the building (its cap) and the full $75,000 of contents (under the $100,000 cap), for $325,000 of program coverage. That leaves $50,000 of building value above the cap — the amount to cover with a private excess-flood policy if you want full protection. A renter in the same building might skip building coverage entirely and insure just their $75,000 of contents.

Risk, pricing and timing

Flood costs depend on your property’s flood risk, elevation and the NFIP’s Risk Rating 2.0 methodology, so an official quote is the only way to get your price. Two practical points matter most. First, don’t wait: NFIP policies generally have a 30-day waiting period, so you can’t buy as a storm bears down. Second, don’t assume you’re safe outside a mapped flood zone — a substantial share of claims come from moderate- and low-risk areas, where coverage is also cheaper. Use the calculator to set your target building and contents amounts, then get a quote from the NFIP or a private flood insurer well ahead of flood season.