Both passport and ID card:
• states the person's identity,
• certifies Polish citizenship.
The passport entitles you to cross the border and stay abroad, while the ID card allows you to travel to:
• European Union member states,
• countries of the European Economic Area,
• states which, by separate decisions, allow crossing of borders on the basis of a valid ID card.
Before leaving, check if your travel documents are valid and check the regulations of the country you are traveling to. Some countries require the traveller to have a passport valid for a minimum of 6 months from the planned date of return to the home country. Check where you can go with your ID card.