The Government health body will promote the move to healthier snacks through the launch of its Change4Life campaign.
Half of children’s seven sugar cubes a day comes from unhealthy snacks and sugary drinks with kids currently consuming three snacks and sugary drinks a day while around a third consume four or more, according to PHE.
Its figures show that each year children are consuming almost 400 biscuits; more than 120 cakes, buns and pastries; around 100 portions of sweets; nearly 70 of both chocolate bars and ice creams; washed down with over 150 juice drink pouches and cans of fizzy drink.
The eight-week Change4Life campaign will offer money-off vouchers towards items including malt loaf, lower-sugar yoghurt and drinks with no added sugar in some supermarkets.
The 100 calorie limit means most of the biggest crisps and chocolate bar brands, along with ice cream and pastries, would not be recommended as daily snacks.
Fruits and vegetables with a calorie count above the threshhold are not included in the guidelines.
Dr Alison Tedstone, chief nutritionist at Public Health England, said: “The true extent of children’s snacking habits is greater than the odd biscuit or chocolate bar.
“Children are having unhealthy snacks throughout the day and parents have told us they’re concerned.
“To make it easier for busy families, we’ve developed a simple rule of thumb to help them move towards healthier snacking – look for 100 calories snacks, two a day max.
Justine Roberts, Chief executive founder of Mumsnet, added: “The volume of sugar kids are getting from snacks and sugary drinks alone is pretty mind-blowing, and it can often be difficult to distinguish which snacks are healthy and which aren’t.
“This rule of thumb from Change4Life will help parents make healthier choices, which can only be a good thing.”
PHE says it is working with the food industry to cut 20% of sugar from the products children consume most by 2020, with work to reduce calories due to start in 2018.
According to data, a third of children are leaving primary school overweight or obese.