E-government is a field where oriented practice is considered crucial for its prosperity. Therefore, best practices are considered among the success factors of e-government portals. To this end, e-government maturity models can be used to provide guidance and guidelines to identify those best practices. After an extensive literature review, we have collected both; the e-government portals' best practices and organized them according to their purposes in an e-Government Portals' Best Practice Model (eGPBPM), and the set of 25 maturity models best practices in two separated previous published studies. The eGPBPM is composed of four best practice categories including: back-end, Web design, Web content and external. Moreover, each maturity model has several stages of maturity and each stage include a set of best practices used to rank the maturity of e-government portals. The goal of this paper is to identify the extent to which e-government maturity models are covering the best practices of the eGPBPM. To achieve this goal, a mapping between the maturity models' best practices for each maturity stage and the best practices of the eGPBPM has been performed. Our findings show that although this set of maturity models are used in practice, they include only some of the e-government portals' best practices and none of them have a full coverage of those best practices.