The largest driving force for pulling fluid from the interstitial spaces back into the capillaries is

The main driving force for pulling fluid from the interstitial spaces back into the capillaries is blood colloid osmotic pressure. The oncotic pressure or as called as colloid osmotic pressure is a classification of osmotic pressure transport to bear by proteins notably albumin in a blood vessel's plasma which is blood or liquid that typically inclines to pull water into the circulatory system.