The article presents the results of research reflecting the essence and properties of courier services, as well as the premises for improving the "last mile" logistics in Poland. Undoubtedly, "last mile" logistics can be treated as a part of distribution logistics and in the era of turbulent development of e-commerce should be the subject of scientific research. There is some ambiguity related to the identification of the essence of courier services as part of the logistics services market. These services are provided by postal operators and significantly affect logistics solutions in the area of distribution and after-sales service. The purpose of the research was to determine the characteristics of courier services in Poland, including their drawbacks, and to indicate the possibility of implementing changes in the "last mile" logistics necessary to eliminate the identified imperfections. The research was focused on solving the following scientific research problem: What services are of key importance in the postal services market in Poland, and what fundamental errors in "last mile" logistics should be eliminated to improve the quality of customer service? The obtained research results allowed to positively verify the following research hypothesis: Courier services are of key importance among postal services, with domestic courier services continuing to dominate. The main drawbacks of current logistics solutions are: damage to parcels; delays in relation to the guaranteed delivery date and loss of parcels. As a result, the essence of courier services as one of the types of postal services was clarified, its essential characteristics were identified, and it was shown that domestic courier shipments will continue to dominate among postal services. The main shortcomings of the logistics solutions currently in use were also identified, namely damage to parcels; delays in relation to the guaranteed delivery date and loss of parcels at the last stage of delivery, which was the basis for pointing out opportunities to improve "last mile" logistics solutions.