This paper evaluates and compares the impact of cellulose ethers (CE) on water transport and porous structure of cement-based materials in both fresh and hardened state. Investigations of the porous network (mercury intrusion porosimetry, apparent density, 2D and 3D observations) emphasize an air-entrained stabilisation depending on CE chemistry. We also highlight that CE chemistry leads to a gradual effect on characteristics of the water transport. The global tendencies brought by CE are: higher water retention, lower capillarity water absorption, lower liquid water permeability as well as higher water vapour permeability. All things considered, we demonstrate that CE chemistry is an important controlling factor on water transport and porous structure evolution.