This product is stored at -20°C and assigned a recommended retest date of 4 years from the date of Quality Release. This date is published in the product Certificate of Analysis. Please see the link below to review a sample or lot specific Certificate:
https://www.sigmaaldrich.com/product/sigma/a7607#product-documentation
Please see the following link to review additional handling and storage information available in the product datasheet:
https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/product/documents/123/627/a7607dat.pdf