Where the data comes from and how we work with it

Sources for Poland

The Polish database holds 196,499 companies (as of 17 September 2026) and is being expanded. We use publicly accessible sources only:

The table can be scrolled sideways.

We name business directories as a source without linking to them. We take NIP, REGON and KRS numbers only when one of the sources above gives them. We do not download data directly from CEIDG or the National Court Register, which is why not every record has an identifier.

Coverage of the Polish database

The database is being expanded and its coverage is uneven. Of 196,499 companies, 149,095 are based in the Mazowieckie voivodeship, 36,368 records have no assigned region, and the other voivodeships hold between a few hundred and about 1,500 companies each. We do not claim that our own database contains every company in the register. It does not, however, set the limits of our offer: we prepare company lists for all of Poland and, for each enquiry, state before you order how many records match your criteria. We select the records for an export of one of the fifteen industries for each enquiry, because source categories are inconsistent and some records have no category. Current figures are on the Database status page, and the size of the market in each voivodeship according to GUS on the company data by voivodeship table. What you can download free of charge directly from the authorities is explained in our guide Free Polish company data: CEIDG, KRS and REGON.

Sources for the Czech Republic

For the Czech Republic we deliver data from our own database covering 4,404,295 entities (as of 12 September 2026). Identification data comes from official Czech registers:

• ARES

  Administrative register of economic entities: IČO identification number, name, registered office, legal form, date of establishment and activity by NACE.

  ares.gov.cz

• Commercial register and trade licence register

  Company entries, statutory bodies, business licences.

  or.justice.cz · rzp.gov.cz

• VAT payer register

  VAT registration and the unreliable payer flag.

  adisspr.mfcr.cz

• Insolvency register (ISIR)

  Opened insolvency proceedings.

  isir.justice.cz

Contact data in the Czech database comes from public sources, mainly company websites. Figures by industry are on the Database status page.

How a record is built

1. Collection from sources. Directories, OpenStreetMap and public registers produce a record with a name, address and – where the source gives them – NIP, REGON or KRS numbers.
2. Adding contacts. We take the phone number, general email address and website from the same sources and from company websites.
3. Matching. We combine records from different sources only when their attributes match – most strongly the NIP or REGON number, but also the name and address.
4. Cleaning. We bring phone numbers into a uniform format, check email addresses for formal validity and remove duplicates.
5. Classification. We assign the voivodeship and county from the address. Today a record’s industry comes from the source category; a PKD code only where the source gives one. We assign records to one of the fifteen industries for each enquiry; we do not keep a fixed industry breakdown of the whole database.

Matching is automated and not free from errors. With similar names and no identifier, the risk of wrongly combining records is higher.

Legal framework for using the data

• Email and phone for marketing only with consent. Since 10 November 2024, Article 398(1) of the Polish Electronic Communications Law of 12 July 2024 prohibits using automated calling systems and telecommunications terminal equipment (including phones and email) to send commercial information, including direct marketing, to a subscriber or end user unless they have given prior consent. The provision does not distinguish between consumers and businesses. The export contains no such consent, which is why we do not offer data for email advertising or telemarketing. More: B2B telemarketing and email in Poland after the change.
• Postal mail. Article 398 of the Electronic Communications Law refers to automated calling systems and telecommunications terminal equipment; it does not mention traditional postal items. If the addressee is an individual, the GDPR applies, including the right to object.
• Public register data is open, but not “without conditions”. The right to re-use public sector information (Polish Act of 11 August 2021 on Open Data and the Re-use of Public Sector Information) is limited, among other things, by the protection of personal data (Article 6(2)), and the Act does not override data protection law (Article 7(2)). The body making data available may also set conditions, e.g. an obligation to cite the source (Article 15). The extract from the Central Register of Property Valuers is published on dane.gov.pl under the CC0 1.0 licence; OpenStreetMap data is subject to the ODbL licence. Business directories and professional bodies’ lists have their own terms.
• Personal data. Data on sole traders and on named contact persons is personal data. We process it on the basis of legitimate interests (Article 6(1)(f) GDPR); the information required by Article 14 GDPR is on the GDPR information page, and the right to object under Article 21 GDPR can be exercised on the Objection page.
• Supervisory authorities. The controller is based in the Czech Republic, so the lead supervisory authority is the Czech Office for Personal Data Protection (Úřad pro ochranu osobních údajů, ÚOOÚ). A complaint can also be lodged with the President of the Polish Personal Data Protection Office (ul. Stawki 2, 00-193 Warsaw).
• The buyer’s responsibility. Whoever buys data from us is the controller for their own use of it and needs their own legal basis. We do not provide legal advice.

Known limitations

• Uneven coverage. Most records in our own Polish database currently come from the Mazowieckie voivodeship; other regions are only thinly represented in it. That is why we always give the number of records for a specific enquiry.
• Contacts go out of date. Companies change phone numbers, email addresses and websites; time passes between a change and the update of the source.
• No deliverability check. The number of email addresses is not a number of checked mailboxes; a phone number does not confirm that the subscriber can be reached.
• General addresses. Addresses such as biuro@ or kontakt@ are not the personal contacts of decision-makers.
• Region by address. The voivodeship and county follow from the company address, not from the area where it operates or from individual branches.

Reporting errors

If you find incorrect information in your own record, please let us know – we will correct it.

• Contact formPlease give the company name, address and the incorrect information.
• Objection to processingFor sole traders and other people who want to exercise their rights under the GDPR.
• info@firmowekontakty.plDirect email to the site owner.

Registers and directories are run by their administrators. We correct our own database; a lasting correction also requires a change at the source.