The concentration of red cell 2,3-DPG (2,3-diphosphoglycerate) rapidly decreases during storage. A favourable effect on red cell 2,3-DPG has been demonstrated by rapid cooling of whole blood prior to storage. In our study we have investigated how different methods of cooling whole blood immediately after donation effect 2,3-DPG levels during storage.Thirty-six whole blood units (in 6 groups) of 450ml were collected in 63ml CPD. SAG-M was used as preservative solution for red cell concentrates (RCC). The units in one group were cooled down at ambient temperature, while units in the other groups were cooled down rapidly by different ways immediately after bleeding. Samples from the whole blood units were collected at various days during storage for 2,3-DPG measurements.The decline in 2,3-DPG during the first two weeks of storage was significantly slower in the groups which were cooled down rapidly to 17–18°C within 1h after bleeding (all p⩽0.0001).The rapid fall in 2,3-DPG can be delayed significantly by cooling whole blood units rapidly after bleeding. Most of the methods we used in our study can easily be implemented in daily routine practise in any blood bank.