A police statement last night said the group entered the hotel about midnight and threatened a female employee with a knife and stole cash.
The employee was not injured but was "very shaken" and had been offered victim support.
A man (28) and a woman (25) would appear in the Dunedin District Court today charged with aggravated robbery. A 47-year-old woman would appear in the Christchurch District Court today on a charge of aggravated robbery.
Search warrants were carried out in Dunedin and Christchurch yesterday.
Detective Sergeant Dave Nelson said a regional team effort led to the early arrests.
"... both here in Dunedin and with our colleagues in Christchurch that enabled the alleged offenders to be arrested and charged in such a short period of time."
Further charges were likely and the investigation was ongoing.
