Network slicing is a very important capability in 5G networks to bring up network resource utilization efficiency and deployment flexibility. It thus can enable the fast growth of customer facing services (CFSs) in 5G networks. With it, a wide range of CFSs with diverse QoS requirements can be accommodated in 5G networks. Our research addresses the issue of pricing a 5G end-to-end network slice based on its resource usage. A 5G network slice contains network slice subsets to deliver guaranteed QoS/KPIs to network services. Each network slice subset is a managed group of infrastructure resources, network functions and services. By observing the resource allocation in the network slice subnets, a network slice can be priced in a logical way. At the end of the paper, we will provide charging functions which are able to explore the resource usage of network slicing subnets based on its attributes in order to apply charging equations based on these attributes.