Here's the fact that surprises most homeowners: a standard homeowners policy does not cover flood damage. Water rising from outside your home — storm surge, an overflowing river, heavy rain pooling faster than the ground can absorb it — is excluded on every standard form. Flood insurance is a separate policy, and it's the only way to cover that risk.
Who this is for: anyone who owns a home near water, in a low-lying area, or in a region where heavy rain is common — not just people in a mapped flood zone.
Why home policies exclude flood
Flooding tends to hit whole neighborhoods at once, which makes it hard for a regular insurer to spread the risk. So the industry carved it out decades ago, and the federal government stepped in with the National Flood Insurance Program (NFIP). Your homeowners policy still covers plenty of water damage — a burst pipe, for example — but water that rises from outside is a different policy entirely.
NFIP vs private flood
NFIP policies are backed by the federal government but sold through regular insurance companies and agents, so you can often buy one from a carrier you already know. NFIP coverage for a home currently tops out at $250,000 for the building and $100,000 for contents.
Private flood insurance is a newer, growing alternative. Private policies can offer higher limits, broader coverage (like loss of use), and sometimes better pricing. Some lenders accept private flood in place of NFIP. It's worth pricing both.
The waiting period
An NFIP policy typically takes effect 30 days after you buy it. The main exception: if you're buying coverage in connection with a mortgage closing, it can start right away. The practical takeaway is simple — you can't buy flood insurance when a storm is already on the map. If you're going to want it, buy it on a calm day.
Who should think about it
Flood maps are a starting point, not the whole story. FEMA reports that a meaningful share of flood claims come from moderate- and low-risk areas, and every state has seen flooding. If your home has a basement, sits at the bottom of a slope, or is in a region where storms are getting wetter, it's a reasonable question to ask even if your lender doesn't require it. Renters can buy contents-only coverage, too.
What it covers, and doesn't
Building coverage handles the structure, foundation, electrical and plumbing systems, and built-in appliances. Contents coverage handles your belongings, though items in basements get limited treatment. Flood policies generally don't pay for temporary living expenses (NFIP doesn't; some private policies do), and damage from a sewer backup that isn't caused by a flood needs its own endorsement on your home policy.
Flood insurance is one piece of the picture — comparing a few homeowners quotes side by side is a good way to see how the rest of your coverage fits together.