Under-Insured or Over-Insured? How the Wrong Sums Decide Spanish Claims

Most insurance disputes in Spain are not about whether something is covered. They are about two numbers written on the schedule years earlier: the sum insured, and what the insured thing was really worth on the day it burned, flooded or was written off. Spanish law has a precise rule for each direction of error — infraseguro (under-insurance) quietly cuts every claim you make, and sobreseguro (over-insurance) makes you pay, year after year, for cover that can never pay you back. Both are avoidable, both give you enforceable rights, and both follow you into places you might not expect: the state’s catastrophe fund pays flood and earthquake claims on exactly the sums your policy declares, and even a car insured as the wrong version settles from the wrong value table. After 25 years arranging home, car and business insurance in Spain, these two traps are behind most of the disappointing settlements we are asked to rescue — so here is the complete guide.

What under- and over-insurance actually are

Spanish insurance contracts are governed by Ley 50/1980, de Contrato de Seguro, and its logic starts from one principle, stated in Article 26: insurance can never be a source of enrichment. You are made whole for what you actually lost — never more. Article 27 adds the other side of the coin: the sum insured is the maximum the insurer will ever pay per claim. Those two articles between them create both traps:

• Infraseguro (under-insurance) exists when, at the moment of a loss, the sum insured is lower than the real value of the insured interest — a villa insured for €200,000 that would cost €320,000 to rebuild, a shop insured for average stock that is holding its Christmas peak, a car declared as a cheaper version than it is.
• Sobreseguro (over-insurance) exists when the sum insured is notably higher than the real value — classically, a home insured at its market or purchase price when only the construction, not the land, can ever be destroyed. Our companion guide to calculating your home’s rebuild cost covers that side in detail.

Neither is fraud, in the normal case. Both are usually the residue of an honest guess made years ago — and both have precise legal consequences.

Under-insurance: how the proportional rule cuts your claim

Article 30 contains the sentence that decides more Spanish claims than any other: if the sum insured is below the value of the interest at the time of the loss, the insurer indemnifies the damage “in the same proportion in which the sum covers the insured interest”. The formula the loss adjuster applies is simple:

OCU, Spain’s consumer organisation, uses this example: a home really worth €150,000 but insured for €100,000 — 67% covered — suffers €30,000 of damage. The payout is €20,000. Three points about that example are worth engraving:

• It applies to partial claims. The house did not burn down; a €30,000 loss still lost a third of its value. This is the misunderstanding at the heart of most under-insurance: people insure low because “the whole house will never go”, but the rule does not wait for a total loss. The sum insured must be enough to rebuild or replace everything, damaged or not, or every claim shrinks.
• It is mechanical, not punitive. The adjuster is not punishing you; the premium you paid only ever bought a fraction of the risk, so the policy pays that fraction. OCU has documented a real settlement cut by 28% for exactly this.
• It is negotiable before the loss, never after. Article 30 itself allows the parties to exclude the proportional rule in the policy — that is what seguro a primer riesgo (first-loss cover) is, and many policies also carry a tolerance margin (commonly 10–15%) before the rule bites. Whether yours does is a matter of wording — one of the first things we check when we review a policy.

How common is it? A landmark Spanish study found the average home insured 32% below its real value (€107,000 declared against €142,000 real), industry estimates put around 10 million Spanish dwellings under-insured to some degree, and roughly 40% of owners never review the policy after signing it. Construction costs rising more than 40% since 2020 have silently widened every one of those gaps.

Over-insurance: paying for cover that cannot pay you

The opposite error feels safer and is merely expensive. Insure a €300,000-rebuild home for €500,000 because that is what you paid for it, and Article 31 produces three consequences:

• At claim time you receive the actual damage — nothing more. The extra €200,000 of capital is not a bigger payout waiting to happen; under Article 26 it is legally incapable of paying out. The Supreme Court restated this as recently as September 2025: a family whose insured house burned down claimed the policy’s €362,250 sum as a lump sum, and the Court confirmed the sum insured is only a ceiling and a premium-calculation reference — the payout is the damage actually caused, expert-valued, never the number on the schedule.
• You have the right to demand a correction. Either party — that includes you — can require the sum insured and the premium to be reduced, and the insurer must refund the excess premium it has collected. Very few policyholders know this right exists.
• Bad faith voids the contract. Deliberately over-insuring (hoping a loss pays out more than the thing is worth) makes the contract ineffective — the good-faith insurer keeps the premiums.

And here is the honest part, said plainly on our rebuild-cost guide too: over-insurance is good business for insurers and agents — premium is charged on the capital, and even the small compulsory Consorcio surcharge is charged per mille on the declared sums. We set capitals at the real value because it is the only correct number, not because it maximises the premium. If your current policy’s capital was set from a purchase price, a bank valuation including land, or a guess, you are very likely paying for capital that can never be claimed.

Two policies on one home: the double-insurance rules

A surprising number of expat homes carry two policies at once — the one the bank arranged at the mortgage signing and the one the owner bought later. That is not automatically wasteful (different covers can complement), but the law on it is widely misunderstood:

• You never collect twice. Where the same policyholder insures the same interest against the same risk with several insurers over the same period (seguro cumulativo, Art. 32), each claim is shared between the insurers pro rata to their sums insured — capped, always, at the actual damage.
• You must tell each insurer about the other unless the policies say otherwise; deliberately hiding it, where it creates over-insurance, can cost you the claim entirely.
• Different policyholders are a different case. The Supreme Court confirmed in 2025 (STS 493/2025) that the pro-rata rule requires the same policyholder on both contracts — a landlord’s policy and a tenant’s policy on the same building are not cumulative insurance, and the insurer cannot use the other policy to cut its own payout.
• If the two sums together notably exceed the value, the over-insurance rules of Article 31 apply to the total — you can and should cancel or reduce one. We review doubled-up situations constantly for holiday-home and landlord clients; the usual outcome is one properly-calculated policy and a premium saving.

The other trap: declaring the risk wrong (the regla de equidad)

Article 30 is about the sum. A second, less-known rule is about the facts. Under Article 10, before the contract you must answer the insurer’s questionnaire truthfully about everything that bears on the risk — and Article 11 obliges you to notify changes that aggravate it during the contract. If a claim happens and the declared facts turn out to be wrong:

• Honest error: the payout is reduced by the regla de equidad — in proportion to the difference between the premium you paid and the premium the true risk would have carried. Paid 60% of the right premium? Expect roughly 60% of the claim.
• Deliberate or grossly negligent misdeclaration: the insurer is released from paying at all.

This is not a theoretical clause. In 2022 the Supreme Court (STS 144/2022) applied it to cut a claimed indemnity of €3.63 million to €801,696 — confirming that the reduction applies even when the insurer has lost its separate right to rescind the contract. The everyday versions are smaller but constant: the “occasional” driver who is actually the daily driver, the home declared as a main residence that is really a tourist let, the business activity described too narrowly. The fix costs nothing: declare reality, and update the declaration when reality changes.

Motor: the wrong car version, drivers and modifications

People think of under-insurance as a property problem. Spanish car insurance has its own version of it, and it hides in the vehicle description:

• The version defines the value. Spanish insurers identify a car by make, model and versión (trim and engine), usually resolved from the number plate, and both the premium and the insured value flow from the professional valuation tables for that exact version. Insure a BMW 320d as the cheaper 318d and in a total loss every figure is computed from the wrong, lower base: on a valuable car the difference runs to thousands of euros, money that simply never arrives. In write-offs the settlement ladder (new value in the first years, then valor venal — a table value that falls to a small fraction of the price as the car ages) is applied to the declared version, so a wrong declaration under-insures the car at every age. At claim time the adjuster identifies the real car from its VIN in seconds — the mismatch always surfaces.
• Undeclared regular drivers. Spanish courts have repeatedly upheld reduced or refused payouts where the real habitual driver — typically a young son or daughter — was not the declared one. Occasional lending is covered; systematic use by an undeclared higher-risk driver is a misdeclared risk.
• Accessories and modifications. Non-factory extras — alloys, audio, tow bars, roof boxes — are typically only covered if individually declared with make, model and price; most theft covers exclude undeclared accessories entirely. Camper conversions are the extreme case: fixed furniture, solar panels, batteries, heating and gas installations must be expressly declared (and the conversion homologated on the ficha técnica), or the habitation side of the vehicle is effectively uninsured. The same declare-it principle runs through van, motorbike and fleet policies.
• The finance gap. A total-loss settlement at valor venal can land below the outstanding finance on the car — you can owe money on a vehicle that no longer exists. That is a solvency gap rather than under-insurance proper, and it is what GAP cover exists for — worth discussing when a financed car is insured.
• Where values genuinely are agreed: classic car policies work on an agreed value precisely to avoid table-value arguments on appreciating cars — the same logic that makes agreed-value hull terms standard on yachts.

If a motor claim does go wrong, our guides to how car claims are settled in Spain and making a motor claim walk the process step by step — and we manage our clients’ claims ourselves on 966 461 625.

Home, contents and business: where the capitals go wrong

Buildings (continente)

The full method — square metres, rates, pools, walls, terraces and the Lorca earthquake’s brutal audit of a whole town’s sums insured — lives in our dedicated rebuild-cost guide. The one-line summary: insure the rebuild cost of everything on the plot, never the market price, and round up.

Contents (contenido)

Contents under-insurance is quieter but just as mechanical. The capital should be the new replacement cost of everything in the home — and the classic omissions are wardrobes full of clothing, the linen cupboard, tools and bikes in the garage, and anything in drawers. Two schedule details decide real settlements: whether the policy pays new-for-old (valor de reposición a nuevo) or deducts depreciation, and the sub-limits on jewellery and valuables — typical Spanish policies cap per-item and per-claim amounts and require higher-value pieces to be itemised, with better limits when a safe is used. Declaring contents low to trim the premium re-creates Article 30 indoors: a €100,000 contents inventory declared as €60,000 turns a €50,000 burglary into a €30,000 payout.

Business capitals

Commercial policies multiply the places a capital can be wrong — and the proportional rule applies to each one separately:

• Stock: settled proportionally against the real value at the time of loss — a seasonal business must insure the peak, not the average, or use a declaration-basis policy. This is standard advice on our shop & retail insurance page.
• Machinery and fittings: declared at today’s new replacement cost, not the depreciated book value in the accounts — post-2021 inflation has silently under-insured plant declared years ago. Relevant to every bar and restaurant, office, hotel and industrial risk we insure.
• Loss of profits: the sum is built from your gross margin applied to projected turnover — declare it low and the same proportional arithmetic cuts the payout. A 2026 Generali-commissioned study found only 18% of Spanish SMEs carry business-interruption cover at all (the EU average is 26%) — for many businesses that cover is the difference between surviving a fire and not.
• Communities of owners: nine in ten Spanish blocks are insured, but frozen capitals, cadastral-value shortcuts and undeclared renovations are endemic — and any shortfall in a claim lands on the owners as a derrama. Details on the community insurance page and in the comunidad owner’s guide.

After a business loss, the process itself is covered in our business claims guide.

How it all affects the Consorcio — Spain’s catastrophe fund

Here is the part almost nobody prices in. Catastrophic events in Spain — extraordinary flooding like the October 2024 DANA, earthquakes, winds over 120 km/h — are paid not by your insurer but by the state-backed Consorcio de Compensación de Seguros, funded by a small compulsory surcharge on every policy (for homes, 0.07 per mille of the sums insured — about €21 a year on a €300,000 capital). Three rules tie the Consorcio directly to your declared sums:

• It covers “the same property and the same sums insured” as your ordinary policy (Art. 8.2 of its statute, RDL 7/2004). It never asks what your home is worth — only what your policy says.
• It applies the proportional rule. The extraordinary-risks regulation (Art. 5.3, RD 300/2004) repeats Article 30 almost word for word: a home 30% under-insured is 30% under-compensated in a flood or earthquake. (Claims practitioners report the Consorcio is tolerant of modest shortfalls in practice, but that is claims practice, not a rule you can rely on.)
• No policy, no payout. The Consorcio only exists for the insured; an uninsured home gets nothing from it after a catastrophe, however severe.

The one mercy: for homes, residential communities and vehicles the Consorcio applies no excess at all on property damage. The scale of what rides on this is now historic: after the 2024 DANA the Consorcio had paid out almost €4,500 million by mid-2026 — over €1,100 million of it to homes and communities — and after the 2011 Lorca earthquakes it paid about €485 million, in both cases strictly against each policy’s declared sums. The full Lorca story — who rebuilt on insurance money and who waited thirteen years for public aid — is told in the rebuild-cost guide; how to file a Consorcio claim is covered in the Consorcio explained.

Your rights — and how to dispute a cut settlement

Everything above sounds insurer-friendly, so let us be equally clear about the other direction. Spanish law and case law give the policyholder real weapons:

• The insurer must prove it. The proportional rule is a defence the insurer raises — and it bears the burden of proving the real value of the interest was higher than the sum insured. An adjuster’s assertion is not proof; a documented valuation is.
• If the insurer set the number, courts have made it own the number. Spanish courts have refused to apply the proportional rule where the sum insured was generated by the insurer’s own systems from data its agent collected — in one fire case a court ordered the full €323,542 indemnity plus penalty interest precisely because the client was never asked to declare a value, only the square metres. Likewise, where a value was documented with invoices at inception and accepted, courts have treated it as the agreed real value — and held that valuation clauses buried in the general conditions which cut the payout after a loss are limitative clauses, unenforceable unless specifically signed (Art. 3). The doctrine is not automatic — other courts have applied the rule where the insurer never actually consented to the capital — but if a professional calculated your sum insured, say so loudly when the rule is invoked.
• You can contract the rule away — in advance or even now. First-loss cover (a primer riesgo), express derogation of the proportional rule, tolerance margins (typically 10–15%) and capital-offset clauses (compensación de capitales — surplus in the buildings capital automatically covers a shortfall in contents, and vice versa, standard in good Spanish home, community and commercial policies) all exist in the market. Article 30 expressly allows the derogation to be agreed after the contract is concluded — so a policyholder who discovers a doubtful capital today can fix it by endorsement today, not at the next renewal.
• Over-insured? Demand the refund. Article 31 gives you the right to have the sum and premium reduced and the excess premium returned — in writing, effective from the demand.
• Disagree with the adjuster? Use Article 38. The law has a built-in expert procedure: you appoint your own perito (if the other side is required to appoint one and fails to within eight days, it is bound by yours); if the two disagree, a jointly appointed third decides by majority within thirty days. The decision binds both sides on the amount unless challenged in court — and the windows are strikingly asymmetric: the insurer has 30 days to challenge, you have 180. Each side pays its own expert and the third is split — unless one side’s valuation was manifestly disproportionate, in which case Article 39 makes that side pay everything.
• Delay has a price — for them. An insurer in unjustified delay owes statutory penalty interest at the legal rate plus 50%, rising to a minimum of 20% a year once two years have passed since the loss (Art. 20). And note your own clock: actions under a damage policy prescribe after two years, so disputes cannot be left to drift.
• Complaints ladder. First a written complaint to the insurer’s customer-service department (the DGSFP will not open a file without it), then — after their answer, or one month of silence for consumers — the DGSFP’s claims service, free and entirely in writing; its report is not binding but filing it suspends the limitation clock, and a favourable one usually moves an insurer. Our complaints page explains the route and the deadlines, and as your agent we run this process for you. Our general claims hub and the line-by-line guides (home, community, business, marine) cover the practical steps.

How to stay out of both traps

1. Calculate, don’t guess. Buildings at rebuild cost (the method), contents from a room-by-room inventory at new prices, stock at peak, machinery at replacement cost, cars by their exact version.
2. Declare reality — and changes to it. New pool, new kitchen, camper conversion, new regular driver, home becoming a rental: each is a call to us at the time, not a discovery at claim time.
3. Round up, never down. Modest headroom costs cents and defeats the proportional rule; Article 31 only concerns sums that notably exceed the value.
4. Let index-linking run from a correct base — it preserves a right number, it cannot fix a wrong one.
5. Review annually, recalculate every few years — and immediately after any works or major purchase.
6. Kill pointless duplicates. Two policies on one home usually means one premium wasted — keep the better one, calculated properly.

Frequently asked questions

Sources & references: Ley 50/1980 de Contrato de Seguro, Arts. 10, 11, 26–32 and 38 (BOE consolidated text); Tribunal Supremo judgments STS 144/2022 (regla de equidad) and STS 493/2025 (seguro cumulativo); Real Decreto Legislativo 7/2004 and Real Decreto 300/2004 (Consorcio statute and extraordinary-risks regulation) and the DGSFP surcharge resolutions; Orden ECC/2845/2015 (Consorcio deductibles); RD 716/2009 Art. 10 and Ley 5/2019 Art. 17 on mortgage-linked policies, with the DGSFP’s published criteria and the Banco de España mortgage guide; OCU and Mapfre consumer guidance on capitals, settlement bases and valuables limits; the Línea Directa infraseguro study and UNESPA home-insurance data; Consorcio de Compensación de Seguros published payment data for the 2011 Lorca earthquakes and the 2024 DANA (consorsegurosdigital.com); Generali España / SDA Bocconi 2026 SME insurance-gap study; Spanish motor-market guidance on version-based pricing, valor venal scales, accessories and camper declarations. Figures are indicative August 2026 guide figures; policy wordings vary — check your schedule or ask us. This guide is general information, not financial advice.