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Data sources

TailsTrails uses open data to suggest the city and neighborhood for the postcode you give us. This page lists each source, the license it is published under, and the credit it asks for. We're grateful to everyone who publishes it.

How we use it

We use these sources only to match a postcode to a place and to suggest the neighborhoods nearby. We adapted the data to do that: we combined sources, estimated how many residents of each postcode live in each neighborhood, and removed or renamed some names.

The original publishers provide their data as is, without any warranty, and they have not reviewed or endorsed TailsTrails. A suggested neighborhood can be wrong — you can always choose another one, or none.

Places and postcodes

  • GeoNames — place names and postcodes in all five countries. CC BY 4.0. Geo data © GeoNames.
  • Ordnance Survey, OS Open Names — suburbs in the United Kingdom. Open Government Licence v3.0. Contains OS data © Crown copyright and database right 2026.
  • United States Census Bureau — 2020 population and US ZIP code areas. Public domain.

US neighborhoods

US neighborhood and city boundaries come from Who's On First, which gathers them from many publishers. Data from Who's On First. License.

These publishers' licenses ask for credit:

  • Pediacities — New York City. ODC Attribution License 1.0.
  • Zolk Chicago Neighborhoods Map — Chicago. CC BY 3.0 US.
  • Azavea, Inc. — Philadelphia. CC BY 3.0 US.
  • Washington Post — Washington, DC. CC BY.
  • Quattroshapes — neighborhoods and city boundaries in many US cities. CC BY 2.0.
  • Atlanta Department of Planning and Community Development — Atlanta. CC BY 4.0.
  • Baltimore Mayor's Office of Information Technology — Baltimore. CC BY 3.0.
  • Denver Department of Community Planning and Development — Denver. CC BY 3.0.
  • City of Cambridge Geographic Information System Department — Cambridge, Massachusetts. CC BY.

Other boundaries come from publishers who place them in the public domain or under licenses that ask for no credit, including Zetashapes, Mapzen, the United States Census Bureau, and the cities of Los Angeles, San Francisco, Seattle, San Diego, Oakland, Portland, New Orleans, Santa Barbara, Boston and San Jose.

Quebec and Montréal

  • Institut de la statistique du Québec — the town of each Quebec postcode, and where each Montréal postcode sits. Institut de la statistique du Québec, CP Territoires – Fichier de géolocalisation des codes postaux basé sur le Référentiel québécois des adresses (RQA) du ministère des Ressources naturelles et des Forêts. CC BY 4.0.
  • Ville de Montréal — Montréal neighborhood boundaries (Quartiers de référence en habitation). CC BY 4.0.

The rest of Canada

  • Statistics Canada — the town each Canadian postal area outside Quebec belongs to. Adapted from Statistics Canada, Census Forward Sortation Area Boundary File and Geographic Attribute File, 2021 Census. This does not constitute an endorsement by Statistics Canada of this product. Postal code is an official mark of Canada Post Corporation. Statistics Canada Open Licence.
  • City of Vancouver — Vancouver's 22 local-area boundaries, the neighborhoods we suggest for a Vancouver postcode. Contains information licensed under the Open Government Licence – Vancouver. Open Government Licence – Vancouver.

Something wrong?

If we suggest the wrong neighborhood, pick the right one or choose "None of these" when you sign up. To report a problem with the data, contact us.