The SNP leader will announce her party’s intention to expand the current provisions which cover children aged four to seven in primaries 1-3.
She suggests the move, which had previously been suggested by Education Secretary John Swinney in November last year, could save families hundreds of pounds a year.
It comes a day after Scottish Labour leader Anas Sarwar said all pupils should benefit from free meals during the summer holidays through catch-up clubs in a bid to tackle holiday hunger.
Ms Sturgeon is expected to say: “The Covid-19 pandemic has been tough for everyone – that’s why so much of our focus in government has been to help families get by in tough times.
“All children in primaries 1 to 3 already benefit from access to free school meals, saving families around £400 per child per year.
“But if re-elected, we will go much further. An SNP government will provide free school breakfasts and lunches to every primary school pupil in Scotland, all year round, and for all children in state-funded special schools in Scotland. This will eventually save them an estimated £650 a year per child.
“That will make an enormous difference to families in every corner of the country — but even this will not be the limit of our ambition.”
There will also be plans to pilot free nutritious school breakfasts in secondary schools, which the party hopes will lead to a universal breakfast provision rolled out for older pupils.