How many years of stable and regular income obtained in the territory of Poland should be demonstrated in order to obtain a long-term resident's EU residence permit?

You must demonstrate that you have a stable regular income for the three years immediately preceding your application, or two years, if you are in Poland on the basis of a Blue Card.

Remember that as of the date of issuing the decision on the long-term resident's residence in the EU, you must also prove that you have such income.