How long does blood stay ''good''?

I’m just curious, how long can donated blood stay transplantable?

42 days. That’s why it is urged that all blood donations stop for a while. They have enough for now, and blood you give today will go to waste. Wait a month.

'Preciate the help.

Just wanted to add that the 42 days is for blood that is treated and stored properly. Untreated blood has a pretty short shelf life, which is why many local hospitals don’t do blood donations – they don’t have the facilities to handle large amounts of blood.

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Answered on 9/11/2001: Shelf Life of Human Blood
Answered on 9/12/2001: Blood Storage

There were also one or two other on-topic, but ultimately irrelevant duplicate threads.

Since this question has been answered so recently, I’ll close this thread.

bibliophage
moderator GQ