Families sending their sons to Canberra Grammar School will fork out $21,040 in fees and levies this year, while daughters attending Canberra Girls Grammar School will cost their parents $20,050.

But the biggest increases have affected schools further down the pay scale with fees jumping about six per cent for students studying at Burgmann Anglican School and Daramalan College.

Overall, rising private school fees have been less severe than a year earlier, with the average increase from 2014 to 2015 hovering around four per cent.

Fees and levies have barely changed at Covenant College, with final-year students paying about $50 more than their predecessors.

Covenant College and St Mary MacKillop College are the only two schools with fee changes under or close to the inflation rate, at 0.8 and 2.3 per cent, respectively.

Annual underlying inflation is expected to come in at 2.1 per cent when official December quarter figures are released next week, according to TD Securities/Melbourne Institute.

Burgmann Anglican School's 2014 fees, in contrast, were 12 per cent higher than the previous year to meet the demands of the rapidly-growing school.

School fees are set to skyrocket over the next two decades. The cost of privately educating a Canberra child born in 2015 from preschool to Year 12 is expected to climb to almost half a million dollars, according to the Australian Scholarships Group's Planning for Education Index.

Sending a child through the territory's government school system is expected to be almost eight times cheaper at $53,564, according to the survey released on Tuesday, and closer to $207,732 for children in systemic or religious schools.

The index took into account the varying costs of educating a child starting kindergarten or early childhood education in 2019 and completing Year 12 in 2032, including extra expenses like excursions and uniforms.

Good Shepherd Microfinance CEO Adam Mooney said it was these extras costs that were placing financial strain on parents and sparking a rise in no-interest loans.

"Over the last five years demand for our loans for buying computer equipment for education-related purposes has tripled - we've had 2500 to 3000 loans primarily for computers and laptops," he said.

"In the classroom there's increased pressure on the whole education system - user-pays as much as possible. The take up of tablets and laptops is increasingly high."

Mr Mooney, whose organisation offers no-interest loans through providers across Australia for essential goods and services, said it was difficult to differentiate between demand and societal drivers.

However, many clients with education-related costs were also microfinancing more essential items like beds for their children.

Care Inc director Carmel Franklin agreed education was becoming a huge expense that particularly shook families on lower incomes at the beginning of the school year, coming off the back of Christmas.

She said the projected rise in fees over the next two decades would place extra pressure on families already juggling essential expenses.

"There's definitely more pressure now," she said.

"What I think is concerning families is simply feeling their children have missed out. There's this expectation to provide a lot of activities for children as part of their education and a lot of these are not free."

School funds to support families having difficulty meeting costs and no-interest loans were some of the options for families on a modest income, she said.

Australian Education Union ACT secretary Glenn Fowler said the extra money spent on a private education was a poor investment when it came to academic performance.

Association of Independent Schools of the ACT executive director Andrew Wrigley said although costs factored into decisions around education, parents were investing in an education that was the best fit for their child.