Data sources

Every published value is tied to an identified source. National postal operators remain the authority of reference.

40,977postal codes — United States (40,977 localities)

11,150postal codes — Spain (37,866 localities)

6,085postal codes — France (37,252 localities)

10,812postal codes — Germany (23,295 localities)

2,377postal codes — Austria (18,904 localities)

3,162postal codes — Algeria (15,951 localities)

969postal codes — Tunisia (4,868 localities)

1,325postal codes — Morocco (1,325 localities)

GeoNames attribution

Algeria’s postal data (place names, wilayas, codes, coordinates) comes from GeoNames and is used under the Creative Commons Attribution 4.0 licence. GeoNames provides this data “as is”, without warranty of accuracy or completeness. Changes made by CodePostalPro are described in the methodology.

United States

GeoNames — Postal code dump — US.zip (United States)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (postal codes, place names, administrative hierarchy, coordinates)
Licence: CC BY 4.0
Attribution: des États-Unis postal data: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

40 977 codes ZIP, 51 États (dont DC), 29 540 villes, comté indiqué pour chaque code. Les codes militaires APO/FPO (sans État) et les îles Marshall sont exclus. Un code ZIP est une zone de distribution postale, pas une limite administrative : il peut couvrir plusieurs villes ou comtés.

U.S. Census Bureau — American Community Survey 5-year estimates by ZIP Code Tabulation Area (2023): population, median household income, median age, households, housing units, median home value, median gross rent, per-capita income

Address: https://www.census.gov/programs-surveys/acs
Type: official-statistics
Role: secondary (demographics by ZIP code)
Licence: Public domain (U.S. Government work)
Attribution: Population, median income and median age: U.S. Census Bureau, American Community Survey (ACS) 5-year estimates.
Obtained on: —
Last checked: August 21, 2026

A ZCTA is the Census Bureau approximation of a ZIP code area, not the USPS delivery route itself; a few hundred ZIP codes have no matching ZCTA. Census-suppressed values are not shown.

GeoNames — General gazetteer dumps — cities1000.txt (populated places with IANA time zone), timeZones.txt (offsets), countryInfo.txt (country facts)

Address: https://download.geonames.org/export/dump/
Type: open-data-dump
Role: enrichment (time zone per locality, country facts)
Licence: CC BY 4.0
Attribution: Time zones and country facts: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

Each locality's time zone is that of the nearest GeoNames populated place (1,000+ inhabitants) within 60 km; in single-zone countries every locality gets the national zone directly. Country facts (capital, population, area, currency, calling code, postal-code format) come from countryInfo.txt and are GeoNames' own compilation.

North American Numbering Plan Administrator (NANPA) — Central Office Code Assignment Records — utilized codes, all states (NPA-NXX with rate centre)

Address: https://nanpa.com/reports/co-code-reports/cocodes_assign
Type: official-administrator-report
Role: enrichment (telephone area codes per city and ZIP)
Licence: Public report published by the FCC-designated numbering administrator; factual assignment data
Attribution: Area codes: NANPA Central Office Code Assignment Records.
Obtained on: August 21, 2026
Last checked: August 21, 2026

NANPA assigns prefixes to rate centres (telco billing localities), not to ZIP codes. Each city is matched to its rate centre(s) by name within the state; cities without a rate centre of their own take the codes of the nearest matched city within 40 km and are marked as derived. ZIPs inherit their city's codes, ordered by how many prefixes each code has. Only assigned, in-service prefixes are counted, so newly activated overlays appear on the day NANPA lists them. A ZIP and an area code are different geographies: near a boundary, both codes may be in use.

U.S. Census Bureau — 2020 ZCTA to county relationship file (land and water area per ZCTA)

Address: https://www2.census.gov/geo/docs/maps-data/data/rel2020/zcta520/
Type: open-data-dump
Role: enrichment (land area and population density per ZIP)
Licence: Public domain (U.S. federal government work)
Attribution: Land area: U.S. Census Bureau, 2020 ZCTA relationship files.
Obtained on: September 19, 2026
Last checked: September 19, 2026

Land area is for the 2020 ZCTA, the Census approximation of the ZIP area. Density is ACS population divided by this land area (water excluded).

U.S. Census Bureau — 2020 ZCTA to 119th Congressional District relationship file

Address: https://www2.census.gov/geo/docs/maps-data/data/rel2020/cd-sld/
Type: open-data-dump
Role: enrichment (congressional district per ZIP)
Licence: Public domain (U.S. federal government work)
Attribution: Congressional districts: U.S. Census Bureau, 2020 ZCTA relationship files (119th Congress).
Obtained on: September 19, 2026
Last checked: September 19, 2026

A ZIP can span districts; every district covering at least 1 % of the ZCTA land is listed, largest first, within the ZIP’s own state. District 00 is an at-large seat; 98 a non-voting delegate.

U.S. Census Bureau — 2020 ZCTA cartographic boundary file (1:500,000 generalized, from TIGER/Line)

Address: https://www.census.gov/geographies/mapping-files/time-series/geo/cartographic-boundary.html
Type: open-data-dump
Role: enrichment (boundary map per ZIP)
Licence: Public domain (U.S. federal government work)
Attribution: Boundaries: U.S. Census Bureau, 2020 ZCTA cartographic boundary files.
Obtained on: September 21, 2026
Last checked: September 21, 2026

Maps show the 2020 ZCTA outline, generalized by the Census to 1:500,000 and further simplified for display (~150 m tolerance). A ZCTA approximates USPS delivery routes; it is not a legal boundary, and small enclaves or holes are omitted.

USDA Agricultural Research Service / Oregon State University PRISM group — 2023 Plant Hardiness Zone Map — official ZIP-code lookup tables (CONUS, AK, HI, PR)

Address: https://planthardiness.ars.usda.gov/
Type: open-data-dump
Role: enrichment (USDA planting / hardiness zone per ZIP)
Licence: Public domain (U.S. federal government work, produced with OSU PRISM)
Attribution: Hardiness zones: USDA-ARS / OSU PRISM, 2023 Plant Hardiness Zone Map.
Obtained on: September 22, 2026
Last checked: September 22, 2026

The zone (e.g. 7b) reflects the average annual extreme minimum temperature for 1991–2020, in 5 °F half-zone bands. This is the same ZIP lookup table the USDA site uses — not a spatial approximation. A zone describes winter lows only; it says nothing about frost dates, summer heat or rainfall.

OpenStreetMap contributors — Amenity, shop and leisure places (via the Overpass API)

Address: https://www.openstreetmap.org/copyright
Type: open-data-dump
Role: enrichment (counts of mapped places per ZIP — displayed only, kept separable from the core database and excluded from the API)
Licence: Open Database License (ODbL) 1.0 — © OpenStreetMap contributors
Attribution: Place counts: © OpenStreetMap contributors, ODbL.
Obtained on: September 21, 2026
Last checked: September 21, 2026

Each place (node, way or relation centroid) is assigned to the 2020 ZCTA containing it. OpenStreetMap is community-maintained: counts reflect what volunteers have mapped and completeness varies by area, so figures are minimums, not official totals. This ODbL-licensed layer is stored separately and never merged into the core database or served by the API.

NOAA National Centers for Environmental Information — U.S. Climate Normals 1991–2020, monthly (temperature and precipitation, by station)

Address: https://www.ncei.noaa.gov/products/land-based-station/us-climate-normals
Type: open-data-dump
Role: enrichment (monthly climate normals per ZIP)
Licence: Public domain (U.S. federal government work)
Attribution: Climate normals: NOAA NCEI, 1991–2020 U.S. Climate Normals.
Obtained on: September 19, 2026
Last checked: September 19, 2026

Each ZIP shows the normals of the nearest station with complete temperature records within 80 km (50 mi); the station and its distance are stated on the page. °F and inches as published.

Spain

GeoNames — Postal code dump — ES.zip (Spain)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (postal codes, place names, administrative hierarchy, coordinates)
Licence: CC BY 4.0
Attribution: Spain postal data: GeoNames (geonames.org), CC BY 4.0.
Obtained on: September 23, 2026
Last checked: September 23, 2026

37,866 localities and 11,150 distinct postal codes, 19 Comunidades Autónomas (including Ceuta and Melilla), 52 Provincias (admin2). Single-source, not cross-checked; pending an official cross-check (e.g. Correos).

France

GeoNames — Postal code dump — FR.zip (France)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (postal codes, place names, administrative hierarchy, coordinates)
Licence: CC BY 4.0
Attribution: de France postal data: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

37 252 communes et 6 085 codes postaux géographiques, 13 régions (découpage 2016), 96 départements. Les 14 332 lignes CEDEX (codes de distribution d’entreprise, non géographiques) sont exclues : ce ne sont pas des localités. La Poste publie par ailleurs un fichier officiel des codes postaux à intégrer en recoupement.

GeoNames — General gazetteer dumps — cities1000.txt (populated places with IANA time zone), timeZones.txt (offsets), countryInfo.txt (country facts)

Address: https://download.geonames.org/export/dump/
Type: open-data-dump
Role: enrichment (time zone per locality, country facts)
Licence: CC BY 4.0
Attribution: Time zones and country facts: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

Germany

GeoNames — Postal code dump — DE.zip (Germany)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (postal codes, place names, administrative hierarchy, coordinates)
Licence: CC BY 4.0
Attribution: Germany postal data: GeoNames (geonames.org), CC BY 4.0.
Obtained on: September 22, 2026
Last checked: September 22, 2026

23,295 localities and 10,812 distinct postal codes, 16 Länder, 542 Kreise. Single-source, not cross-checked: Deutsche Post Direkt's own postal file is commercially licensed (redistribution not permitted) and was therefore not used; pending an official cross-check.

Austria

GeoNames — Postal code dump — AT.zip (Austria)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (postal codes, place names, administrative hierarchy, coordinates)
Licence: CC BY 4.0
Attribution: Austria postal data: GeoNames (geonames.org), CC BY 4.0.
Obtained on: September 22, 2026
Last checked: September 22, 2026

18,904 localities and 2,377 distinct postal codes, 9 Bundesländer, 95 Bezirke (admin2). Single-source, not cross-checked; pending an official cross-check (e.g. Statistik Austria).

Algeria

GeoNames — Postal code dump — DZ.zip (Algérie)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (noms de lieux, wilaya, coordonnées, code postal)
Licence: CC BY 4.0
Attribution: Données postales : GeoNames (geonames.org), licence CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

15 951 lignes, 3 162 codes, 48 wilayas (découpage antérieur à 2019). Champs utilisés : code postal, nom de lieu, admin1 (wilaya), latitude, longitude, précision. Aucun niveau commune. La numérotation des codes diffère, pour une large part des bureaux, de la liste post-2008 d’Algérie Poste (voir frwiki-dz-list) ; les deux valeurs sont affichées lorsqu’elles divergent.

Wikimedia Foundation — Wikidata — Communes d’Algérie (P31 = Q2989398) : libellés fr/ar, wilaya, code postal (P281), coordonnées, lien Wikipédia

Address: https://query.wikidata.org/
Type: linked-open-data (SPARQL)
Role: cross-check (codes postaux des communes, noms arabes)
Licence: CC0 1.0
Attribution: Wikidata (CC0).
Obtained on: August 21, 2026
Last checked: August 21, 2026

1 614 lignes ; 576 communes comparables avec GeoNames : 169 concordances, 407 divergences (Wikidata suit en général la numérotation post-2008).

Wikipédia (fr) — Liste des codes postaux d’Algérie (compilée à partir d’Algérie Poste, numérotation 2008)

Address: https://fr.wikipedia.org/wiki/Liste_des_codes_postaux_d%27Alg%C3%A9rie
Type: encyclopedic-compilation
Role: cross-check (valeurs alternatives)
Licence: CC BY-SA 4.0 (texte) — les codes postaux eux-mêmes sont des données factuelles
Attribution: Liste des codes postaux d’Algérie, Wikipédia (CC BY-SA 4.0).
Obtained on: August 21, 2026
Last checked: August 21, 2026

2 507 entrées / 2 386 codes. L’article signale lui-même qu’une mise à jour (liste janvier 2021 d’Algérie Poste) est nécessaire. Utilisée uniquement pour afficher les valeurs divergentes et qualifier la vérification.

Algérie Poste — Bureaux de poste / codes postaux (poste.dz)

Address: https://www.poste.dz/customer/bureaux_postaux
Type: official-postal-operator
Role: authoritative reference (non consultée automatiquement)
Licence: Unspecified / factual data
Obtained on: —
Last checked: August 21, 2026

Site injoignable depuis l’environnement de build (connexion refusée) et absent de la Wayback Machine. Reste l’autorité de référence ; une vérification manuelle des bureaux P0 est prévue (voir PROJECT_STATUS.md).

Wikipédia (fr) — Articles des délégations et localités liées (infobox : code postal)

Address: https://fr.wikipedia.org/
Type: encyclopedic
Role: cross-check
Licence: CC BY-SA 4.0
Attribution: Wikipédia (CC BY-SA 4.0).
Obtained on: August 21, 2026
Last checked: August 21, 2026

Certaines infobox citent l’ancien CodePostalPro comme source : ces valeurs ne sont pas considérées comme indépendantes.

GeoNames — General gazetteer dumps — cities1000.txt (populated places with IANA time zone), timeZones.txt (offsets), countryInfo.txt (country facts)

Address: https://download.geonames.org/export/dump/
Type: open-data-dump
Role: enrichment (time zone per locality, country facts)
Licence: CC BY 4.0
Attribution: Time zones and country facts: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

Tunisia

La Poste Tunisienne — données (transcription communautaire) — zipcodes.csv : gouvernorat ; délégation ; localité ; code postal

Address: https://github.com/TangoRythm/Tunisia-Geodata-API
Type: community-transcription-of-official-lookup
Role: primary (hiérarchie gouvernorat > délégation > localité, codes)
Licence: Non précisée par le dépôt — données factuelles (codes postaux) issues du service public de recherche de La Poste Tunisienne (poste.tn/codes.php)
Attribution: Codes postaux tunisiens : La Poste Tunisienne ; structure reprise de la transcription TangoRythm (GitHub).
Obtained on: August 21, 2026
Last checked: August 21, 2026

4 867 lignes, 24 gouvernorats, 261 délégations. Structure identique au service officiel ; la liste des localités de la délégation El Menzah correspond exactement à celle observée dans les archives historiques de CodePostalPro. poste.tn était injoignable (timeout) lors de la construction ; vérification directe à effectuer.

mn-youssef/state-municipality-tunisia (GitHub) — state-municipality.json : gouvernorats et délégations, noms arabes, code postal principal, coordonnées

Address: https://github.com/mn-youssef/state-municipality-tunisia
Type: community-dataset
Role: secondary (noms arabes, coordonnées des délégations, recoupement du code principal)
Licence: Non précisée par le dépôt
Attribution: Noms arabes et coordonnées des délégations : jeu de données state-municipality-tunisia (GitHub).
Obtained on: August 21, 2026
Last checked: August 21, 2026

24 gouvernorats, 261 délégations. Le code principal de chaque délégation P0 figure parmi les codes de la délégation dans la source primaire (17/17).

La Poste Tunisienne — Recherche de code postal (codes.php)

Address: https://www.poste.tn/codes.php
Type: official-postal-operator
Role: authoritative reference
Licence: Unspecified / factual data
Obtained on: —
Last checked: August 21, 2026

Service officiel (formulaire AJAX). Injoignable depuis l’environnement de build le 2026-08-21 (timeout réseau) ; les résultats de recherche ne sont pas archivés. À re-vérifier manuellement pour les 17 délégations P0.

Wikipédia (fr) — Articles des délégations et localités liées (infobox : code postal)

Address: https://fr.wikipedia.org/
Type: encyclopedic
Role: cross-check
Licence: CC BY-SA 4.0
Attribution: Wikipédia (CC BY-SA 4.0).
Obtained on: August 21, 2026
Last checked: August 21, 2026

Certaines infobox citent l’ancien CodePostalPro comme source : ces valeurs ne sont pas considérées comme indépendantes.

GeoNames — General gazetteer dumps — cities1000.txt (populated places with IANA time zone), timeZones.txt (offsets), countryInfo.txt (country facts)

Address: https://download.geonames.org/export/dump/
Type: open-data-dump
Role: enrichment (time zone per locality, country facts)
Licence: CC BY 4.0
Attribution: Time zones and country facts: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

Morocco

GeoNames — Postal code dump — MA.zip (Maroc)

Address: https://download.geonames.org/export/zip/
Type: open-data-dump
Role: primary (postal codes, place names, administrative hierarchy, coordinates)
Licence: CC BY 4.0
Attribution: du Maroc postal data: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

1 325 codes postaux, 12 régions (découpage 2015), 59 provinces/préfectures. Noms de régions normalisés en français/anglais/arabe à partir du code admin1.

GeoNames — General gazetteer dumps — cities1000.txt (populated places with IANA time zone), timeZones.txt (offsets), countryInfo.txt (country facts)

Address: https://download.geonames.org/export/dump/
Type: open-data-dump
Role: enrichment (time zone per locality, country facts)
Licence: CC BY 4.0
Attribution: Time zones and country facts: GeoNames (geonames.org), CC BY 4.0.
Obtained on: August 21, 2026
Last checked: August 21, 2026

General sources

Internet Archive — Wayback Machine CDX (codepostalpro.com)

Utilisée uniquement pour reconstituer l’architecture d’URL historique. Aucun contenu, code HTML, image ou donnée n’a été copié.

GeoNames — Worldwide postal-code dump (allCountries) — bulk tier for countries without curated records

Served only through the API and MCP server, clearly marked tier "bulk" and verification "source-single": these records are taken from one aggregator without the cross-checks applied to curated countries (US, FR, DZ, TN, MA). Directory pages are published only for curated countries.

Report an error

Administrative boundaries and postal codes change, and our sources may contain errors. Documented corrections are welcome: error report form.