--- title: "Seismic zone by municipality — all 7,896 Italian comuni — CSIDIA" description: "Search a municipality and read its seismic zone as published by Italy’s Civil Protection Department, regional sub-zones included. National coverage checked against the official ISTAT list." url: https://csidia.com/en/tools/catastrophe-risk/ lang: en publisher: CSIDIA S.r.l. (https://csidia.com/) --- [Tools](https://csidia.com/en/tools/) # Which seismic zone is your site in? Italy’s 2024 Budget Law requires companies to insure against earthquakes, floods and landslides, and the premium must be set in proportion to risk. Here is the first of the three inputs, the one an insurer cites first: the municipality’s seismic zone. Search a municipality Municipalities covered **7,896** Verification **100% match with the official ISTAT list of Italian municipalities; cross-checked against Lombardy Region open data, with no discrepancy on the municipalities present in both sources.** ## Ground acceleration, by point The seismic zone is administrative and applies to a whole municipality: Milan and Turin sit in the same one. What actually separates two sites is peak horizontal ground acceleration, which Italy’s building code defines point by point on a national lattice of 10,751 nodes. Paste the site’s coordinates: below you get the mesh of four nodes that contains it, how much each one weighs, and the value at the point, computed with the decree’s own formula. Site coordinates (latitude, longitude) Search for a municipality above first: the map then opens on its province, with every municipal boundary, so you can see where you are pointing instead of guessing. - How you get from the nodes to the point is set out in Annex A to the decree of 14 January 2008, which the 2018 building code refers back to: for a point that does not fall on a lattice node, the values may be computed as a weighted average of the values at the four vertices of the elementary mesh containing the point, using the inverses of the distances as weights. That is formula [3] of the decree, and it is the one applied here. Beware of an easy confusion: these are the four vertices of the mesh, not the four nearest nodes — often they are not the same. - What is computed here is the baseline seismic hazard, referred to stiff ground with a horizontal surface (category A). The design seismic action additionally requires the subsoil category, the topography and the nominal life of the works: that remains a designer’s job. - The grid coordinates use the ED50 datum, everyday maps use WGS84: the two differ by roughly a hundred metres, immaterial for an order of magnitude and material for a design calculation. - The lattice has no nodes over Sardinia and the smaller islands because the decree sets a different rule for them: response spectra are defined from values of ag, FO and TC* that are uniform across the whole territory of each island, for every island except Sicily, Ischia, Procida and Capri. Those uniform values are not part of the lattice and are not in the file we publish. [The spectral parameters grid on the Ministry’s portal](https://dati.mit.gov.it/catalog/dataset/parametri-spettrali-sismici) ## The other two hazards are not here yet The law names five events, which are three families: earthquake, flood and landslide. Only the seismic one is here, and not by editorial choice: for flood and landslide there is no national source that can be queried by point. The ISPRA API stops at the municipality, and the polygons must come from the seven river-basin district authorities, with different scales, classes and dates. Stitching them without carrying provenance would produce data less precise than its sources, and we would rather not publish it until it is. ## What this figure is not - It is the administrative figure, the one an insurer cites: it applies to the whole municipality and does not separate two sites kilometres apart. It is not site-level seismic hazard, which is a different quantity, measured as peak ground acceleration. - It is not insurance advice: it does not say whether a policy is adequate, does not estimate a fair premium and recommends no contract. - It is not a survey: it says nothing about the state of a building, its structural vulnerability or expected damage. - It does not discharge the insurance obligation: only a policy does that. ## Source Civil Protection Department, seismic classification of Italian municipalities, stated update May 2025. The “value as published by the source” field carries the original string unaltered, regional sub-zones included. [The seismic classification on the Civil Protection website](https://rischi.protezionecivile.gov.it/it/sismico/attivita/classificazione-sismica) · [Download the normalised dataset (JSON)](https://csidia.com/dati/sismica/sismica-comuni.json) · [The administrative boundaries of municipalities, on Istat](https://www.istat.it/it/archivio/222527) An information tool, not legal advice and not a conformity assessment. The references are the ones cited entry by entry; the text that counts is the official one. The first step ## Book a meeting. Tell us the purpose. We tell you whether an agent or a trained model would do it better than you do today, what it would take (data, compute, time) and which route fits: our infrastructure or yours. If it is not a job for us, we say so. - video call or in person - 30 minutes - free [Book a meeting](https://csidia.com/en/book/?servizio=misura) [or write to engagement@csidia.com](mailto:engagement@csidia.com?subject=First%20meeting%3A%20A%20model%20trained%20for%20your%20purpose) The service A model trained for your purpose An open-weight model trained on your data, on our infrastructure or yours. What it learns stays yours. [What we do](https://csidia.com/en/what-we-do/) [Capabilities](https://csidia.com/en/capabilities/) Page: https://csidia.com/en/tools/catastrophe-risk/ · CSIDIA S.r.l., Vignola (MO), Italy · engagement@csidia.com · index for agents: https://csidia.com/llms.txt