Abuse and Rape Crisis Support Manawatu is reducing its counselling hours after government funding cuts.
ARCS manager Ann Kent said the group was now relying on public donations while continuing to apply for public grants.
ARCS needs $25,000 to maintain its services for this financial year. The organisation has not received any funding for its education programme, which may be the first to go if funds aren't found.
"We are working to prevent sexual abuse, particularly by working in high schools focusing on having healthy relationships. These prevention education programmes will probably be the first service to be cut," Ms Kent said.
She said that Manawatu needed ARCS to provide a specialist service to locals who had been abused.
"About one in four females, and one in seven males are sexually abused. The impact it can have on people's lives in significant - Treasury figures from 2004 estimate sexual abuse costs the country about $2.2 million a year," she said.
Other similar services around the country are also facing cuts. Green Party women's spokesperson Jan Logie addressed the Manawatu issue, saying "there is a funding crisis in the sexual violence support sector".
"Social Development Minister Paula Bennett confirmed that the $20 million Community Response Fund, which had ensured many of these services could stay afloat, had been cut as it was only 'temporary'. She said it was 'tight times'."
The Green Party has also accused National of not fulfilling promises made in regard to sexual violence provisions.
"Ms Bennett could not guarantee the additional funding that the sexual violence support sector needs to continue to help the victims of sexual crime," Ms Logie said.
"Once again, the most vulnerable people have been left out in the cold."
The support network was set up in 1982 as a response to a number of sexual assaults that were occurring and aims to assist both men and women dealing with sexual violence.