The present invention relates to stable formulations of polypeptides, e.g. immunoglobulin single variable domains, in particular immunoglobulin single variable domains directed against von Willebrand Factor (vWF). The invention provides formulations which are stable upon storage for prolonged periods of time and over a broad range of temperatures. The formulations of the invention ensure a high stability of the polypeptide, allowing multiple freeze-thaw cycles without chemical or physical deterioration, and provide stability in relation to mechanical stress, such as shake, shear or stir stress. They are suitable for pharmaceutical and diagnostic preparations and compatible with pharmaceutically acceptable diluents.
