---
title: "Data Sources & Attribution"
product: "Delivery Zone"
version: "1.0"
last_updated: "2026-08-31"
effective_date: "2026-08-31"
status: "current"
---
Data Sources & Attribution — Delivery Zone
Version: 1.0
Last updated: 2026-08-31
Effective date: 2026-08-31
This page describes, at a source level, the reference data Delivery Zone uses to validate
Finnish postcodes and to build its own geospatial dataset, and provides the attribution some of
those sources require. It supplements the Postcode Data Disclaimer,
which explains how these sources are used in a delivery check.
---
1. Postcode Validity and Reference Authority
Posti Group Oyj — Finland's designated postal operator — publishes the Postal Code File
(Postinumerotiedosto), the authoritative reference for which Finnish postcodes currently
exist, their type, and related postcode change information. Delivery Zone uses this reference
information to validate postcodes; it is used under Posti's published service description and
terms of use for postal code services, which permit this kind of use with disclosure of the
source and reference date. This attribution is that disclosure.
Posti is not affiliated with Delivery Zone, does not endorse, certify, or license Delivery Zone,
and is not responsible for how Delivery Zone uses this information. Posti remains the
authoritative source for official Finnish postcode information.
---
2. Delivery Zone's Own Geospatial Dataset
Where a radius (distance-based) delivery rule needs a representative location for a postcode,
Delivery Zone's own versioned geospatial dataset is used when it meets our production confidence
threshold for that postcode. This dataset is built by combining postcode validity information
(Section 1) with the open geographic reference sources listed below. It is Delivery Zone's own
processed output, not a redistribution of any single source, and is not itself licensed to third
parties.
Open geographic reference sources used to build this dataset
OpenStreetMap
Used via a Finland regional extract distributed by Geofabrik.
Licence: Open Database License (ODbL) 1.0.
Attribution: © OpenStreetMap contributors, available under the Open Database Licence —
Statistics Finland — Paavo (postal code area statistics)
Postal-code-area geographic boundary data published by Statistics Finland (Tilastokeskus).
Licence: Creative Commons Attribution 4.0 International (CC BY 4.0).
Attribution: Statistics Finland, Paavo — postal code area open data, CC BY 4.0.
SYKE — Finnish Environment Institute (Ryhti national open address package)
National open address reference data published by the Finnish Environment Institute (Suomen
ympäristökeskus, SYKE).
Licence: Creative Commons Attribution 4.0 International (CC BY 4.0).
Attribution: Suomen ympäristökeskus (SYKE), Ryhti open address data, CC BY 4.0.
We do not redistribute these source datasets themselves — only Delivery Zone's own derived,
processed geospatial dataset is used to power delivery checks, and only delivery decisions (not
raw coordinates or source records) are returned by the API. See the
Postcode Data Disclaimer, Section 6
for restrictions on reconstructing or redistributing data derived from the Service.
---
3. Licensed Fallback Coordinate Source
For radius-based delivery rules on postcodes where Delivery Zone's own dataset does not yet meet
our production confidence threshold, a licensed third-party coordinate source may temporarily be
used as a fallback, where permitted by that source's licence. This is a commercial, proprietary
licence, not an open dataset — the vendor and licence details are documented internally and are
not disclosed on this public page, consistent with the licence's own confidentiality terms. We do
not redistribute this data, and known unreliable records from this source are excluded from use.
---
4. Questions
For questions about data sourcing or this attribution page, contact support@deliveryzone.fi.
---