I just realized we have been using expired G4 sensors for the last couple of weeks, and have 4 more boxes with August or September 14 expiration dates. We also have a HUGE stockpile of sensors with 2015 expiration dates because our supplier has been refilling 1X/week for a long time, and we generally use them for 10 days. I haven't noticed a decline in accuracy but I also wasn't paying close attention until I realized all of this in the last few days. Any firm evidence on how long sensors last past the expiration dates, and any good strategies on what to do with expired sensors? My husband wants to toss them because if we use the currently expired sensors we're basically signing up to use expired sensors in perpetuity, since that will push out when we use the ones with the later expiration dates. I see his logic, but I feel awful about tossing the whole lot if they're accurate, knowing how much they cost.