Walk-ins are accepted for whole blood. I'm not sure how busy they are on other days but Sunday mornings there is usually no wait.
Anything on Trima (2RBC, platelets, or plasma) is treated as appointment first, then walk-ins. Whole blood donations (aka normal donations) are treated mostly the same way. Registration stops at closing time, but anyone in line at closing time will be registered. And we will stay until the last donor is done.
I was able to walk in. I only had to wait a few minutes to donate plasma.
I do platelets, need an appointment, they desperately need platelet donations!
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