It is a person specifically named by another through a written power of attorney to act for that person in particular activities. e.g. filing applications, documents, collecting personal mail etc. The scope of a power of attorney depends on your personal preference or trust. The attorney-in-fact will be able to act on your behalf after submitting a power of attorney to the office. Power of attorney is subject of the stamp duty (17PLN). There is no fee applied if the attorney-in-fact is spouse siblings, ascendants and descendants for the person giving the power.