The change at Bayfield High School was instigated by its pupils when they raised the uniform issue at both junior and senior school councils.
A survey of the school, teachers and parents was conducted last year, resulting in the school deciding to revert to a shirt, tie and blazer combination.
Bayfield assistant principal Caroline Doole said a "strong voice" came from the pupils in support of a "smarter uniform".
The present uniform, based on polo shirts and polar-fleece jerseys, had been in place for 10 years.
Girls wore a navy skirt, junior boys wore navy shorts and senior boys wore navy pants.
The new uniform, which will be phased in from the year 9 and 11 levels next year, would better suit Dunedin's climate, she said.
Juniors will have a navy wool-mix lined skirt or shorts, with a light green, open collared shirt, and v-necked jersey.
Seniors will wear a white shirt with tie and blazer.
Boys will wear wool-blend trousers and girls a wool-blend, lined tartan skirt.
There will also be a choice of wearing a vest or jersey for senior students.
While concerns about costs were raised by parents, the school was doing its best to keep the cost of the new uniform comparative to the old, Miss Doole said.
Logan Park High School has also introduced a blazer for its senior students.
Principal Jane Johnson said the uniform was reviewed two years ago.
Consultation was carried out with the board of trustees, school staff and pupils.
The resounding response from pupils was to introduce a senior uniform to differentiate them from juniors.
The school uniform had been based on a polo shirt, polar fleece top and grey pants for boys, and kilt for girls.
The new, locally made uniform would introduce a white shirt, tie and blazer for boys, and a white shirt and blazer for girls.
Both could wear a black woollen vest and the pants and kilt would be retained.
"It's been very popular.
If they like it, they will wear it well," Ms Johnson said.
Pupil Emma Bennet said she felt "much more presentable" in the new uniform, while Mitchell Henderson believed blazers were "not as rank as the polar fleece".
Paying for the new uniform did not appear to be a big issue for parents, with positive feedback coming from the community, she said.