NSW Police believe they have solved a sex attack case that is now 15 years old.

Two men allegedly entered a home on Church Street, Collarenebri, in the state’s northwest in 1998.

One of the men allegedly sexually assaulted a 54-year-old woman and the pair fled.

A cold case review and new evidence has led investigators to charge a 36-year-old man with aggravated break and enter and aggravated sexual assault.

He has been refused bail to appear before Walgett Local Court on February 11.