A Kapiti Coast woman who stole nearly half a million dollars from her brother's business to fuel her gambling addiction has been jailed for 2-1/2 years.

Ann Denise Lawton, 50, was sentenced in Porirua District Court yesterday after earlier admitting more than 400 fraud charges, taking a total of $452,909 from her brother's Paraparaumu business between 2003 and 2010.

Lawton's lawyer Elliot Lynch told the court she had spent all of the money on pokie machines.

"She was not supporting a lavish lifestyle...She has a serious gambling problem and her offending was fuelled by that."

Lawton was the office manager in her brother's business, Kapiti Diesel, and was able to channel the money into her own account, the court was told.