Victims of sex abuse, forced marriage and female genital mutilation can now receive immediate support at the end of the phone.
Northants Rape Crisis provide the service which is available for all victims or witnesses of domestic violence.
Whether the incident happened minutes or years ago, anyone can call the confidential helpline.
Victims of stalking, harassment, honour based violence and trafficking can also receive support.
Voice, a support service for victims and witnesses, began operating in October and this phone line is a service which develops the support.
Linda Lee, chairman of Voice, said: “This helpline provides support to those who are victims of some of the most dreadful crimes.
“I know that it can be very difficult to take that first step and seek help but I want to encourage victims to call.
“Skilled and sympathetic advisors are waiting to give you the help and advice you need. Please pick up the phone.”
Police and crime commissioner Adam Simmonds, who launched the helpline yesterday, said: “For too long victims have been in the background of the criminal justice system.
“I am determined that the people of Northants should have the best, most comprehensive support service in the UK.
“Providing services such as this new helpline is one of the most important and exciting parts of my role.”
It is the first service to provide specialist support across a range of violence and abuse across the county.
Call the helpline on 0300 222 5930 Monday to Friday, 10am to 3pm, and on Saturday, 10am to noon.
On Monday, Wednesday and Thursday, the line is also open from 6pm to 8pm.