Same requirements for licensing and accreditation.
You can always evaluate each using the same criteria.
Cost roughly the same.
Good quality preschools and daycare centers will offer activities designed to stimulate your child’s physical, social and cognitive development.
Preschool is specifically designed for children between the ages of 2 and ½ and 5 or 6; Daycare is aimed at children of many different ages (infant to elementary school age).
Preschools have more limited hours (typically 3 hours at a time, 2 to 5 times a week). On the other hand, some daycares offer their services during the full working day, making it a desirable choice for working moms.
Curriculum: most preschool organized around a specific educational approach (i.e. Montessori, Waldorf), whereas most daycares are viewed as being more custodial than educational.