The proportional rule explains why a settlement can be cut when the sum insured falls behind. This is about a different disagreement: you accept the sum insured is correct, and you still think the insurer's assessor has under-valued the loss itself. That figure is not final, and there is a specific, contractual way to challenge it.
Start with a written challenge, before anything else
The insurer's first figure comes from a loss adjuster the insurer instructed and pays. Ask, in writing, for the basis of the calculation: what was measured, what evidence was used, and which policy clause or exclusion produced the reduction. A surprising number of disagreements are resolved at this stage, once the actual reasoning is on paper rather than a total in an email. Keep the request narrow and factual — you are asking how the figure was reached, not yet disputing it.
The perito de parte: naming your own assessor
If the written explanation does not resolve it, Portuguese insurance law itself provides for exactly this situation. Article 50.º of the Regime Jurídico do Contrato de Seguro (RJCS, Decreto-Lei n.º 72/2008) — Perícia arbitral — allows the determination of the causes, circumstances and consequences of a loss to be committed to arbitral experts named by the parties, on the terms set out in the policy or agreed afterwards; unless the parties agree otherwise, that determination binds insurer, policyholder and insured alike. In practice, this is what "peritagem" means on a Portuguese property policy: each side names an assessor — the insurer's own loss adjuster, and your perito de parte, an independent assessor you appoint and pay — and if the two disagree, the policy wording sets out how a third arbitrator is brought in.
Two things are worth confirming in writing before you commission anyone: what the specific policy wording says about how the third arbitrator is chosen and paid, and whether there is a time limit for invoking the mechanism after the insurer's figure is issued. Article 50.º sets the legal basis; it leaves the operational detail to the contract, so the governing clause in your own policy is what actually controls it.
Where CIMPAS fits
CIMPAS — the Centro de Informação, Mediação e Arbitragem de Seguros — is a private, non-profit alternative dispute resolution body, authorised by the Ministry of Justice, that exists specifically to resolve conflicts arising from insurance contracts. It works in three stages: information, mediation and, if that does not settle it, arbitration. It is open to policyholders directly, sits alongside the insurer's own internal complaints process and the courts rather than replacing either, and is a genuinely different route from the perito de parte mechanism above — the arbitral experts in peritagem are appointed under the policy itself to settle a factual disagreement about the loss; CIMPAS is an independent body a policyholder can bring the wider dispute to.
Livro de Reclamações and the ASF
Two routes exist outside the contract itself. Every business in Portugal that deals with consumers, insurers included, must provide access to a Livro de Reclamações — physical or digital — and a complaint entered there is forwarded to the relevant regulator. It creates a dated, official record; it does not itself decide the dispute or fix a settlement figure.
The ASF, Portugal's insurance regulator, supervises insurers' conduct and takes complaints directly through its own reporting channel. It is the right route once you have raised the disagreement with the insurer in writing and it remains unresolved, or where the complaint concerns how you were treated rather than a figure a second assessment could settle. It does not replace peritagem as the way to price a specific loss.
What a broker actually does in this process
Adler & Rochefort is not the insurer, does not adjudicate the dispute, and does not decide the settlement figure. What we do: keep the correspondence organised so the sequence of what was said and when is not lost, confirm what the specific policy wording says about the arbitration clause before you commission an assessor, and help you frame the written challenge so it asks the right question the first time. Appointing and paying your own perito de parte, and any escalation to the Livro de Reclamações or the ASF, remain yours to instruct.
Disagree with a settlement figure?
Send us the insurer's assessment and the policy wording. We will tell you in writing what the arbitration clause actually says for your policy.
Adler & Rochefort is a commercial brand of Ownizo, Unipessoal Lda., registered with the Portuguese Insurance and Pension Funds Supervisory Authority (ASF) under no. 425591790/3. General information only, not personalised advice or legal advice; the arbitration mechanism and time limits described here vary by policy wording and should be confirmed against your own contract.
More on this subject: Underinsurance and the proportional rule · How Adler & Rochefort supports a claim