Westport schools are calling for a review of their new decile ratings, saying much has changed in the town since the census that gave rise to them.

Westport North's acting principal, Cath O'Loughlin, says the school's rating has risen from four to five, meaning a drop in funding of around $15,000 a year.

She believes other schools in the district will be in a similar situation.

The decile ratings are provisional and will be finalised next week.