The break-in happened shortly before 1am this morning (07/12) when the offender or offenders forced entry through the main front doors of the shop in Calne Road.
It is believed that they made off with two cash drawers from the tills.
Police officers were at the scene within ten minutes of receiving a call about the incident and carried out a thorough search of the area, but could not locate the suspects.
However, witnesses have reported seeing two men running away from the scene in the direction of Preston Lane.
We are appealing for anyone with information, including anyone who may either live in the area or have been driving through around the time of the burglary, and may have private CCTV or dash cam footage which could assist our enquiries.
If you can help please call Wiltshire Police on 101, quoting crime reference 54200121136. Alternatively you can call Crimestoppers anonymously on 0800 555111.