This follows a major sport, leisure and culture consultation exercise held in January where over 1,000 people responded.
What people said during the consultation helped key decision makers when it came to setting the prices to use its facilities during the next financial year.
Besides free swimming for under 3’s, the council will increase the time of the casual swim from 40 minutes to one hour for just 20p more. And the cost of a family swim falls from £9.55 to £8.
Councillor John Briggs, NLC’s cabinet member for sport, leisure and culture, said: “A big part of getting it right is listening to what people tell us - which we have done.
“The free casual swim for toddlers aged three and under will benefit many parents and carers as will the extended duration for the adult casual swim.
“And there’s good news for families.
“We have reduced the price of a family swim to £8.
“All this represents excellent value for money and gives people a better deal at a time when money is tight for many people.”
Casual swimming for under 16’s remains free.