It can even keep eggs fresh for awhile without any refrigeration and extend refrigeration by a week at least. 1  Eggs can remain edible for even longer than a month, but freshness (egg yolk that sits firm and high, and a thick viscous egg white) will be noticeably less after two weeks. Eggs can remain edible for even longer than a month, but freshness (egg yolk that sits firm and high, and a thick viscous egg white) will be noticeably less after two weeks. 2  If eggs start out as Grade AA, they remain AA for only two weeks if properly refrigerated. 3  After that, they'll be Grade A for another 2 weeks.