Abstract: Provided are methods of using fluid loss control additives that comprise a water-soluble polymer with hydrophobic or hydrophilic modification. In one embodiment, a method of providing at least some degree of fluid loss control during a subterranean treatment is provided. In an example of such a method, the method may comprise providing a treatment fluid comprising an aqueous liquid and a fluid loss control additive, the fluid loss control additive comprising a water-soluble polymer with hydrophobic or hydrophilic modification; and introducing the treatment fluid into a well bore that penetrates a subterranean formation, wherein there is at least a partial reduction in fluid loss into at least a portion of the subterranean formation from the treatment fluid and/or another aqueous fluid introduced into well bore subsequent to the treatment fluid.