Hospitals get blood primarily from outside suppliers, not from collecting it themselves. About 45% of the roughly 14 million units of whole blood available annually in the U.S. comes from the American Red Cross, another 42% from independent community blood banks, and only about 11% from hospitals’ own collection efforts. The remaining 2% is imported. Once collected from volunteer donors, every unit goes through processing, rigorous testing, and careful storage before it ever reaches a patient’s veins.
Where the Blood Comes From
The U.S. blood supply system grew somewhat haphazardly, with blood centers developing independently across different regions rather than following a single national plan. In areas the Red Cross covers, it handles collection through mobile blood drives and permanent donation centers. Everywhere else, one or more community blood banks fill the role. These independent centers operate regionally, sometimes serving just a handful of hospitals in a metro area, sometimes covering an entire state.
Hospitals that do collect their own blood (accounting for that 11% share) typically run small donor programs tied to their transfusion services. But most hospitals find it more practical to purchase blood from a large supplier that handles the collection, testing, and processing at scale.
What Happens After Donation
A standard whole blood donation yields about one pint. At the collection site, the donation bag and several small test tubes are each labeled with an identical barcode so they can be tracked together through the system. The donation is placed on ice and transported to a processing center, while the test tubes head to a laboratory.
At the processing center, most whole blood donations are spun in a centrifuge to separate them into usable components: red blood cells, platelets, and plasma. Plasma can be further processed into products that help blood clot. Red cells and platelets go through an additional step where white blood cells are removed, which significantly reduces the chance of a transfusion reaction in the recipient. Each separated component is packaged as a standardized “unit,” the consistent quantity doctors order when a patient needs a transfusion.
One donation, in other words, doesn’t just help one person. It can be split into multiple components that go to different patients with different needs.
Testing for Safety
While the components are being separated, the test tubes from the same donation undergo about a dozen screening tests. The FDA requires that every unit of donated blood be tested for a long list of infectious agents: HIV (types 1 and 2), hepatitis B, hepatitis C, syphilis, West Nile virus, Zika virus, a parasitic disease called Chagas disease, babesiosis (a tick-borne infection), and HTLV (a virus linked to certain leukemias). Some screening also checks for cytomegalovirus, a common virus that poses risks to patients with weakened immune systems.
These tests use a combination of antibody detection (looking for the immune system’s response to an infection) and nucleic acid testing (detecting the genetic material of the pathogen itself). Nucleic acid testing catches infections earlier, during the window period before the body has mounted a detectable immune response. Results are transmitted electronically to the processing center within 24 hours. Only units that pass every test are labeled as suitable for transfusion and moved into storage.
Storage and Shelf Life
Each blood component has its own storage requirements and expiration clock, which is a major reason hospitals can’t simply stockpile unlimited quantities.
- Red blood cells are refrigerated at 1 to 6°C and last up to 42 days, depending on the preservative solution used. Some formulations allow only 21 or 35 days.
- Platelets are the most perishable component. They’re stored at room temperature (20 to 24°C) on gentle agitators that keep them from clumping, and they expire after just 5 days.
- Plasma is frozen at minus 18°C or colder and remains usable for up to one year.
- Frozen red blood cells stored at minus 65°C or colder can last up to 10 years, though this method is typically reserved for rare blood types.
That five-day window for platelets is the tightest bottleneck in the entire blood supply. It means hospitals and blood centers must constantly replenish platelet stocks, and any disruption in donations, even for a few days, can create shortages quickly.
How Blood Gets to the Hospital
Blood suppliers ship to hospitals around the clock, 24 hours a day, 7 days a week. During transport, products must stay within strict temperature ranges set by federal regulation. Red blood cells travel between 1 and 10°C. Platelets are kept close to room temperature (20 to 24°C). Frozen plasma must remain at minus 18°C or colder. Specialized coolers, insulated containers, and temperature monitoring devices are used to maintain these conditions during transit.
Most hospitals receive routine shipments on a regular schedule, often daily, to maintain their on-site inventory. Emergency or “stat” orders can be placed at any time when a trauma case, major surgery, or unexpected bleeding event pushes demand beyond what’s on hand.
Managing Inventory Inside the Hospital
Once blood arrives, it’s stored in the hospital’s blood bank, which is usually a section of the laboratory department. Staff there face a constant balancing act: keep enough units on the shelves to handle emergencies, but don’t overstock components that will expire before they’re used.
Despite the availability of mathematical models for optimizing blood inventory, most hospital blood banks rely on experienced staff who set target stock levels based on typical usage patterns and adjust them daily. The core principles are straightforward: use the oldest units first (a first-in, first-out approach), review stock levels every day, and track everything meticulously. Staff monitor inventory both through software systems and by physically checking what’s on the shelves to make sure the two match. Monthly performance reports help teams spot trends in usage and waste.
Wastage from expired units is one of the key metrics blood banks track. Platelets, with their five-day shelf life, are the hardest to manage. Red blood cells offer more flexibility with their six-week window, but even so, hospitals try to order just enough to avoid discarding units that age out unused.
What Hospitals Pay for Blood
Hospitals don’t get blood for free. The average acquisition cost for one unit of red blood cells is roughly $200. That covers the blood center’s expenses for recruiting donors, collecting the blood, processing and testing it, and delivering it. But the true cost to a hospital is significantly higher once you factor in labor: the technologists who receive and store the blood, perform compatibility testing before each transfusion, and monitor patients during and after the procedure. These associated costs are harder to pin down but can substantially exceed the purchase price of the unit itself.
Hospitals with high transfusion volumes negotiate contracts with their suppliers, and pricing can vary based on location, the type of product, and how rare the blood type is. Specialty products, like units screened for cytomegalovirus or irradiated components for immunocompromised patients, typically cost more.