We’ve gathered everything that matters in one guide: jurisdictions, taxes, payment systems, and the most common mistakes entrepreneurs face when entering new markets.
What is a PESEL in Poland and how to obtain it?
PESEL (Polish Powszechny Elektroniczny System Ewidencji Ludności)— is a unique personal identification number in Poland, consisting of 11 digits. It functions similarly to Ukraine’s RNOKPP (Tax Identification Number) or the U.S. Social Security Number (SSN).
Structure of the PESEL
- The first six digits represent the date of birth (year, month, day) with an encoded century indicator.
- The next four digits form a sequential number, where the second-to-last digit indicates gender: even for female, odd for male.
- The final digit serves as a control number.
Purpose of the PESEL
The PESEL is required for registering a place of residence in Poland, accessing medical insurance and social services, opening a bank account, obtaining official employment, paying taxes, and receiving government documents or benefits.
Who can obtain a PESEL
Polish citizens receive a PESEL number automatically at birth. Foreign nationals can obtain one when registering their place of residence in Poland or when required to interact with public authorities, for example, to pay taxes, receive assistance, or work legally.
For example, Ukrainian citizens can apply for a PESEL either in person at their local Urząd Gminy or Urząd Miasta (Municipal Office) in Poland, or remotely through authorized representatives. The PESEL number is issued immediately.
What is the Polish Profil Zaufany, and how to obtain it?
Profil zaufany (Trusted Profile)— is an electronic signature in Poland issued free of charge by the government. It is not a physical card or flash drive, but an online identifier linked to your login and password. It allows you to confirm your identity online, access e-government services, and sign electronic documents.
With Profil Zaufany, you can:
- Sign official documents online without visiting an office (urząd).
- Submit tax declarations.
- Register a business in Poland.;
- Apply for various certificates, extracts, and permits.
- Use government e-services such as gov.pl, ePUAP, ZUS, e-Zdrowie, and eRecepta.
- Obtain extracts from public registers (KRS, CEIDG).
- Book medical appointments and review vaccination or prescription records.
How to obtain and verify Profil Zaufany
- Online via a bank. If you hold an account with a Polish bank that supports the service (e.g., PKO BP, Pekao, mBank, ING, and others), you can create your Profil Zaufany directly through online banking.
- Through an office (Urząd Gminy, Urząd Skarbowy, or ZUS). You need a PESEL number and must complete an application on the gov.pl portal or in person, then verify your identity at a service point (with your passport).
The Profil Zaufany is valid for three years and can be renewed online free of charge.
NIP in Poland
NIP from polish Numer Identyfikacji Podatkowej)— is the Tax Identification Number in Poland. It is used to identify taxpayers in dealings with tax authorities, banks, and other institutions. The NIP is assigned to both sole proprietors (jednoosobowa działalność gospodarcza, JDG) and legal entities such as companies and organizations. It consists of 10 digits and is issued by the Krajowa Administracja Skarbowa (KAS), which is the Polish Tax Administration.
For private individuals in Poland, the PESEL number is used instead of a NIP.
A NIP is mandatory only for those conducting business activities or holding tax obligations in Poland.
REGON in Poland
REGON from polish (Rejestr Gospodarki Narodowej)— is a number in Poland’s National Official Business Register. It is assigned by the Główny Urząd Statystyczny (GUS), which is the Central Statistical Office of Poland. The REGON number is used to identify businesses in statistical, administrative, and official registers. It typically consists of 9 digits for companies or 14 digits for separate business units.
CEIDG in Poland
CEIDG from polish (Centralna Ewidencja i Informacja o Działalności Gospodarczej)— is the Central Register and Information System on Economic Activity in Poland. It records sole proprietors(jednoosobowa działalność gospodarcza), and partners in civil partnerships(spółka cywilna). The Ministry of Development and Technology of Poland maintains the register. CEIDG is public and accessible online, allowing anyone to verify the existence of a business.
With CEIDG, you can:
- Register, modify, or close a business.
- Obtain a NIP and REGON (issued automatically upon registration in CEIDG).
- Submit applications to update business details (address, types of activity, etc.).
- Check information about a registered entrepreneur.
VAT in Europe
VAT (from english (Value Added Tax) — is an indirect tax applied at every stage of the production and sale of goods or services but ultimately borne by the final consumer.
If a company holds a valid VAT number, it is entitled to reclaim paid VAT and, in certain cases, required to charge and remit VAT on incoming transactions.
VAT obligations can arise both within individual countries and across the European Union. VAT UE (Value Added Tax European Union) refers to the EU-wide system of value-added taxation. EU member states operate under a harmonized VAT framework regulated by EU directives, while each country determines its own specific tax rates.
The VAT UE number is a special identifier for VAT-registered businesses within the EU. It is used for cross-border business-to-business (B2B) transactions between companies in different member states. This number enables the application of the “reverse charge” mechanism, under which VAT is not charged by the seller but instead accounted for by the buyer in their own country.
You can easily check if a VAT UE number is valid using the (VAT Information Exchange System)VIES on the EU’s official website
Every EU country sets its own VAT rates and registration requirements, so knowing the rules where you operate helps keep your business compliant and efficient. How it works: Cross-Border VAT with reverse charge.
For example, if a company in Poland sells a service to a company in Estonia, the Polish seller includes the buyer’s VAT number on the invoice. To apply the reverse charge mechanism, meaning VAT is not charged on the invoice, the seller verifies the buyer’s VAT number through the VIES system. If the number is validated, the transaction is completed without VAT on the invoice, and the buyer accounts for the tax in their own country.
One Stop Shop (OSS) in the European Union
OSS (complex. One Stop Shop)— is a special system for simplified VAT payment within the European Union. Introduced in July 2021, it was designed to make compliance easier for businesses selling goods or services to consumers (B2C) across multiple EU countries.Previously, a company had to register for VAT in every EU country where it sold goods or services. With OSS, only a single registration in the company’s country of tax residence is required. Through this system, businesses submit one VAT return, and the tax authorities of that country distribute the VAT to the respective EU member states where the sales occurred.
Types of OSS:
- Union OSS – for companies registered within the EU.
- Non-Union OSS – for companies based outside the EU (for example, from Ukraine) that provide services to consumers in the EU.
Example: OSS in Practice. An e-commerce business establishes a company in Poland and registers for OSS there. It sells goods to consumers in France, Germany, and Spain, charging VAT on these sales. Once per quarter, the company submits a single VAT return in Poland through the OSS system. The Polish tax authorities then distribute the collected VAT to the respective countries: France, Germany, and Spain.
NIF in Romania
NIF from romanian (Număr de Identificare Fiscală)— is the tax identification number issued by the Romanian tax authority, the National Agency for Fiscal Administration (Agenția Națională de Administrare Fiscală – ANAF), to both individuals and legal entities.
For Romanian citizens, the role of NIF is fulfilled by the CNP (Cod Numeric Personal – personal identification code). For foreigners without a CNP, ANAF assigns a NIF specifically for tax purposes. For legal entities, the NIF typically coincides with their CUI (Cod de Identificare Fiscală / Cod Unic de Înregistrare).
The NIF is used for tax registration, accounting, paying taxes and fees, and identification in official financial and legal documents.
In summary, the NIF serves as a universal tax number in Romania, though its underlying code depends on the entity’s status; which could be citizen, foreigner, or company.
CUI in Romania
CUI from romanian (Cod Unic de Înregistrare)— is the unique company registration code in Romania. It is assigned to legal entities — such as companies, associations, and foundations — after registration with the Romanian Trade Register and confirmed by the tax authority (ANAF).
The CUI serves as the company’s identification code for tax and accounting purposes. It often coincides with the company’s NIF (tax identification number) and is used on all official documents, including contracts, invoices, and tax reports.
CUI is equivalent to Ukraine’s EDRPOU or Poland’s NIP.
When registering a business in Romania, the company receives a CUI immediately after registration in the Trade Register, which identifies it to the government and business partners.
NIF in Spain
NIF (Número de Identificación Fiscal) is the tax identification number in Spain:
- For Spanish citizens, the NIF corresponds to their DNI (Documento Nacional de Identidad).
- For foreigners, it is issued as an NIE (Número de Identificación de Extranjero), which also functions as their NIF.
- Companies are assigned a separate NIF for legal entities.
The NIF is used for paying taxes, opening bank accounts, registering businesses, signing contracts, and purchasing property or vehicles.
Think of NIF as Spain’s main tax number, similar to Ukraine’s RNOKPP or the U.S. TIN.
UTR in the United Kingdom
UTR (from english (Unique Taxpayer Reference)— is a unique tax identification number in the United Kingdom. It is issued by HMRC (Her Majesty’s Revenue and Customs) after registering an individual or business as a taxpayer. The UTR is used to identify taxpayers within the HMRC system and is required for submitting tax returns. It can be assigned to individuals (self-employed persons, sole traders, partners) as well as to UK companies (Ltd).
ITIN in the United States
ITIN (Individual Taxpayer Identification Number) is a tax identification number issued by the IRS (Internal Revenue Service) in the United States. It is provided to individuals who need to file U.S. tax returns but are not eligible for a Social Security Number (SSN).
An ITIN is required for foreigners who have income from U.S. sources (for example, from property rental or investments), for family members of U.S. residents who cannot obtain an SSN, and for entrepreneurs or freelancers outside the U.S. who need to report income in the U.S.
An ITIN does not grant the right to work in the United States and does not serve as proof of legal immigration status. It is solely a tax identification number used by the IRS to identify individuals for tax purposes.
How to obtain an ITIN
- Complete Form W-7 — the official application for an ITIN, indicating the reason for applying (for example, filing a U.S. tax return).
- Submit a federal tax return (Form 1040, 1040-NR, etc.).
- Provide documents proving your identity and foreign status (usually a passport is sufficient).
Documents can be submitted by mail to the IRS, through an authorized agent who verifies the documents, or in person at a U.S. Taxpayer Assistance Center.
With WoBorders, you can expect your ITIN in 6–8 weeks.
SSN in the United States
SSN SSN (Social Security Number) is issued by the Social Security Administration (SSA) in the United States. It is a key identifier used not only for social security benefits but also within the financial and tax systems.
An SSN is required to work in the U.S. (employers must have the employee’s SSN), for tax payment and reporting, accessing social benefits and pensions, opening bank accounts, obtaining credit and mortgages, health insurance, and other government programs.
All U.S. citizens receive an SSN automatically. It is also available to permanent residents (Green Card holders) and some temporary residents with work authorization, such as those on work visas.
Unlike an ITIN, an SSN confirms the right to work and provides access to government programs. It is also essential for building a credit history in the United States.
EIN in the United States
EIN (from english Employer Identification Number) is a tax identification number for employers in the United States, issued by the IRS (Internal Revenue Service). It serves as the primary tax ID for businesses.
For individuals, SSN or ITIN is used, while businesses are identified with an EIN. The number consists of 9 digits formatted as XX-XXXXXXX.
An EIN is required to identify an American company for tax payments, filing corporate tax returns, hiring employees, and opening business bank accounts in the United States. EINs can be issued to U.S. companies (LLCs, Corporations, Partnerships), non-profit organizations (foundations, trusts), and sole proprietors, particularly if they have employees or open business bank accounts. Foreign companies can also obtain an EIN if they conduct business in the U.S. or have U.S. tax obligations.
To obtain an EIN in the United States, an application must be submitted to the IRS. Even a foreign company without a U.S. office can apply by submitting Form SS-4 (the official EIN application) along with the company registration documents.
