People have been urged to give blood after stocks were depleted during the bad weather.
The NHS has appealed for blood and platelet donors to visit walk-in centres or book appointments for next week.
Stocks across the UK have been depleted after many people could not travel to their appointments because of the snow and ice.
Mike Stredder, director of Blood Donation for NHS Blood and Transplant, said: "The recent poor weather caused the cancellation of sessions in snow hit areas and meant we collected less blood than we needed, particularly Group A, Group O and B positive donations.
"Seriously ill patients need blood every day and they rely on the generosity of people making time to donate.
"So, we are appealing for existing donors to check the weather before they travel but, if it's safe for them to get out, we need them to come along to a session and donate if they are able.
"Please take action now and walk in and donate - you will save lives."
Hospitals need 6,000 units every day across England to treat patients in need.