Postal Code Services

Postal Code Services are free files that provide up-to-date information about postal codes and addresses in Finnish municipalities and postal code areas. You can use them to keep your company’s address data current and to make it easier to manage mailing lists or address registers. The files don’t include street names or map data, but they offer a reliable base for tasks like updating your customer database.

Files to be downloaded

The Postal Code Data File contains Finnish postal codes that are valid as addresses, along with their basic information.
The Basic Address File contains all Finnish (excluding Åland Islands) postal codes that are valid as addresses, streets and municipalities. If a street is divided into several postal codes, the correct postal code is indicated by building numbers.
Information about changes in postal codes over the previous month.

Download the file of your choice

Read the service description and terms of use. The description contains file names and record descriptions, for instance. When transferring the files or service documents, the service description and terms of use must always be delivered, too.

Frequently asked questions

Posti aims to increase demand for the services and make them more easily available, as well as widely spread correct postal code and address data. Posti hopes that this improves the quality of addresses on mail shipments.

Read the service description and terms of use. The service material is available for download from Posti’s website posti.fi/webpcode

On the website, go to the postal code services’ start-up page (see above), and become familiar with the instructions and material.

Go to the page of the desired service.
Read the instructions (e.g. the name of the downloaded file) and click the service link.
In the service view that opens, click the name of the desired file.
Open or save the file in a desired location when so prompted by your browser application.

The Postal Code File is updated every day (except Sundays) and Basic Address File once a week on Saturdays. Currently, Postal Code Changes is updated once a month, on the third day of each month.

Posti recommends that the data is updated as frequently and quickly as possible in your address details.

The services are no longer available upon a separate order. Instead, the material is freely available at the Posti website. At the website, you can also download the service description, which presents the situation in more detail.

Now that the services are free of charge, the delivery channels will be made simpler and as costeffective as possible. As a result, we have selected self-service channels as the delivery method.

Posti has sent a notification to customers who have been frequent subscribers to the services via e-mail or letter.

The information can be disclosed but, in this case, the current service description and terms of use must also be delivered to the third party.

There may be a technical problem in the systems or data connections of Posti or the customer. In this case:

You can try again later.
You can attempt another channel (if the website is unavailable).
You can contact Posti's Corporate Customer Service tel. +358 200 77000.

The files are produced only once, and have been named so that international operators can also recognize and identify them easily. The service descriptions available through the online service offer more detailed information.

PCF Postcode File BAF Basic Address File POM changes

The date signifies the material’s extraction date.

Yes. When updates are made, older files are moved to the server’s archive folder (./arch). You can download datasets from there for about three months back.

Files are compressed for two main reasons:

Consistency – large address datasets need to be compressed anyway.
Technical functionality – compression prevents files from opening directly in the browser during manual download.

Download the file to your computer and, if needed, extract it using a common decompression tool (e.g. 7-Zip or WinZip).

Note: The latest file is also available uncompressed in the “unzip” subfolder.

These product names have become synonymous along the way. In future, the service which forwards changed information will be referred to as Postal Code Changes.

The data files use the Unix format, with LF (Line Feed) as the line break character. Some programs – like Notepad in Windows – don’t recognize this correctly, which can make the file look confusing.

Try opening the file in WordPad or Excel instead. You can find more detailed instructions on our website if needed.

The file extension of uncompressed files is .dat. It is possible that the file type has been linked by default to an application that handles the file incorrectly (e.g. Microsoft Office 2010).

You should link the file to, for example, NotePad or WordPad or open the file transferred to the work station directly in the aforementioned applications or a similar application. If necessary, contact IT support.