There is disclosed an aqueous formulation comprising(a) a bleach stabilizing component,(b) a salt of an organic carboxylic acid and(c) a preservative.The novel formulation is suitable for use as bleaching liquor for cellulosic fiber materials and is distinguished by a superior stabilizing action, a very good capacity for binding heavy metal ions, a good inhibition of crystallization, and the treated fiber materials have very good rewettability. A significant advantage of the novel formulation is its good biodegradability.