"Once mixed in solution, the TB 500 should be used as soon as possible. Any unused portion should be refrigerated (NOT frozen) immediately at 39F (4C). Stored this way, it will remain potent for 1-2 weeks. See below for further storage information."
What my fav supplier has listed... But they say it's good up to 14 days once reconstituted
I just been shooting the whole bottle regardless. Even though they say it's still good I'd rather do a higher dose and wait longer between shots to make sure I'm not letting any product get degraded. I've heard of one shot a month maintenance with tb500. So again I prefer to shoot it fresh and just give it extra time if trying to spread my money out etc...