The children, aged between 10 months and 14 years, were placed in foster homes on Monday by social workers.
The women, who live together with the children in Dorking, Surrey, were questioned by police and social workers when they returned home on Wednesday. Surrey police and social services said in a joint statement: 'Police have completed a criminal investigation and there is no evidence to take proceedings.'
The two women, who cannot be identified for legal reasons, have denied leaving the children alone at home. They say they made arrangements for neighbours to look after them and that they wanted their children back.
The joint statement indicated that the children were likely to remain in care for the time being. It added: 'However, the joint investigation into the care of the children will continue until next week.'
The women - thought to be staying at an unknown address - said they had no comment to make.