Buildings and Contents Insurance Calculator
Buildings insurance covers the physical structure of your home — walls, roof, fixed fittings — while contents insurance covers what is inside it, and most homeowners need both. Buying them as a single combined policy rather than two separate ones typically costs less overall, since insurers generally offer a discount for bundling the two together rather than a customer buying identical protection from two separate policies. This calculator estimates the combined cost of both based on your property and the level of cover you need.
Buildings & Contents Insurance Calculator
Estimate the right level of buildings and contents cover for your home and see your combined premium range (2025 UK rates).
Why Buy Buildings and Contents Together
A combined policy from a single insurer commonly saves in the region of 8% compared with buying buildings and contents separately, partly because it reduces the insurer’s own administrative overhead of managing two separate policies for the same property, and partly because it is a standard incentive used to win a larger share of a customer’s insurance business. Beyond the price, a combined policy also simplifies claims where damage affects both the structure and its contents at once — a burst pipe damaging both a ceiling and the contents beneath it, for example — since only one claim needs to be made rather than two separate ones with two different insurers.
There is also a practical continuity benefit worth mentioning: renewing a single combined policy each year is one date to track and one insurer to deal with, rather than two separate renewal dates that can drift apart over time and end up costing more collectively than either would if properly aligned and compared together.
What Each Half Actually Covers
Buildings cover is based on rebuild cost — what it would cost to reconstruct your home from scratch, including labour and materials — which is usually quite different from its market value, since land value is not part of a rebuild estimate. Contents cover is based on the total value of everything you would need to replace inside the property, from furniture and electronics to clothing, and is priced as a percentage of that total sum insured rather than the property’s size or type. Getting either figure wrong in either direction causes a real problem: underestimating leaves you underinsured if you need to claim in full, while overestimating means paying for more cover than you actually need.
A useful way to sense-check a contents figure is to walk through the property room by room, roughly totalling the replacement cost of furniture, electronics, clothing and other belongings, rather than guessing a single round number. Most people are surprised by how quickly the total adds up once every room, not just the obviously valuable items, is properly counted.
The Levers That Move Your Premium
Several factors shift the estimate meaningfully. Property type matters — a detached house costs more to insure than a semi-detached one of similar rebuild value, since a detached property has no shared walls to limit certain types of damage, while a flat typically costs less, reflecting a smaller footprint and often shared building-level protections. Risk level, based on factors like location and flood history, can swing the premium considerably in either direction. Security measures such as a monitored alarm system reduce the estimate, while minimal security increases it. Raising your voluntary excess — the amount you agree to pay toward any claim before the insurer contributes — consistently lowers the premium, since it shifts some of the smaller, more frequent claim risk back onto you.
A Practical Comparison
A semi-detached house with a £200,000 rebuild cost and £35,000 of contents, average risk, an alarm fitted and a £250 excess, comes out to a modest combined annual premium built from a buildings figure around 0.15% of rebuild cost and a contents figure around 0.4% of contents value, less the combined-policy discount. Raising the voluntary excess to £500 or £1,000 trims the buildings portion further, at the cost of paying more out of pocket if a claim is ever made — a genuine trade-off between a lower ongoing premium and less protection against smaller claims specifically.
When Separate Policies Make More Sense
A combined policy is not automatically right for everyone. Renters generally only need contents cover, since buildings insurance is the landlord’s responsibility — our Contents Insurance Calculator covers that on its own. Leaseholders in a flat often have buildings cover arranged and paid for collectively through the freeholder or management company as part of service charges, meaning only contents insurance needs to be bought separately in that situation. And anyone whose current buildings and contents needs are unusually different in scale — a modest rebuild cost alongside high-value contents, or the reverse — may occasionally find better individual pricing by shopping the two separately rather than assuming a bundle is always cheaper. Our Home Insurance Calculator covers general standalone home insurance if a combined policy is not the right fit for your situation.
Frequently Asked Questions
How do I find my rebuild cost, not my property’s market value?
Rebuild cost calculators are available from organisations such as the Building Cost Information Service (BCIS), and many insurers will also estimate it during a quote based on your property’s size, type and location, rather than requiring you to research it independently.
Does accidental damage cover come as standard?
No — accidental damage is usually an optional add-on for both buildings and contents cover, protecting against things like a spilled drink on a carpet or a DIY mishap that damages a wall, rather than being included in a standard policy by default.
What happens if I underinsure my contents?
Many insurers apply “average” — if your contents are insured for less than their actual total value, a claim payout can be reduced proportionally, even for a single item, so it is worth reviewing your sum insured periodically rather than leaving it unchanged for years.
Does a higher excess always save money?
Generally yes, but only up to a point that is comfortable for you — the excess needs to be an amount you could genuinely afford to pay toward a claim without financial strain, so the saving needs to be weighed against that practical limit rather than chosen purely to minimise the premium.
Are high-value items like jewellery automatically covered?
Often only up to a set limit per item under standard contents cover — particularly valuable individual items, such as jewellery or art, may need to be specifically listed and separately valued to be fully covered.
Does a security system always reduce my premium?
A monitored or professionally installed alarm system typically reduces the estimate, since it lowers the likelihood of a successful burglary claim, though the specific reduction depends on the type and standard of security fitted rather than security being present or absent alone.
Important Information
This calculator provides an estimate for general information purposes only and does not constitute insurance advice or a quote. Actual premiums are set by individual insurers based on their own underwriting criteria and may differ from the figures shown here. For an accurate quote, compare policies directly with insurers or a broker. See our Disclaimer for further information.