Amana Christian Primary School, in Mosgiel, was not in danger of closing, but principal Roslyn King said she had been working voluntarily as principal, manager and one of its two teachers since it opened in 2000.
"It's not viable to employ a principal, as well as the staff we have," she said.
"We manage. We offer a choice in education and we feel that it is essential.
"But it's a very difficult road because there is very little [Government] money provided to private schools. Private doesn't mean rich, at all."
Mrs King said she survived on her husband's income and did her job because she had "a vision and a passion" for Christian education.
She declined to say what the school's annual fees were, but said the aim was to make them affordable for anyone wanting a Christian education.
Private schools had struggled financially for years because the pool of Government funding had not expanded with the growth in private school rolls, she said.
The tightening economy had made little difference to the situation in Otago because parents were still looking for Christian education as an option.
The Christian private school movement was stronger than ever and Amana's roll was expected to increase from 14 last year to about 20 at the start of school later this month, she said.
Auckland's Hilltop Primary School closed last week, making its nine teachers redundant, after enrolments fell from 50 fee-paying pupils to an expected 1.
The union for private schools, the Independent Schools Education Association, said of the 50 schools it worked with, six were struggling and two others were at risk of closing.
President Bruce Owen said as the economy started to tighten, many parents were pulling their children from private education.
Southern Lakes Christian School (Queenstown) principal Melody Hart agreed the latest financial climate had not affected private schools in Otago.
She was expecting the roll of the composite school to increase to 22 pupils at the start of this year - up two from last year - and because of the "transitory" population of Queenstown, numbers could rise to 30 during the year.
"We've always had financial constraints but for us, with faith in God, we are continuing as normal."
Mrs Hart said pupils' parents paid a compulsory fee of about $1300 a year, plus a donation of about the same amount.
The school also received $1000 a pupil each year from the Government.
The school was "eagerly anticipating" the Government's promised increase in the financial contribution to private schools.
"It's only fair because we all pay the same taxes, so why can't all schools - private and State - receive the same funding and resources from the Government."
Education Minister Anne Tolley was not available for comment on how much would be funded and when the money would be made available.
