Utilizing all-atom simulations with explicit solvent, the authors model hydrophilicsurfacesinteracting across water at a fixed chemical potential. They extract the hydration forces acting between the surfaces and assess force fluctuations as well as interlamellar water number fluctuations. The trends obtained from the simulations are captured by a continuum-based description with effective model parameters. The significance of fluctuations depends on surfacehydrophilicity and rigidity. The authors show that the force fluctuations play an important role in kinetic processes in systems with lateral sizes smaller than several tens of nanometers.