Couple of different ways to do it - take your pickINSERT INTO MasterList(ComputerName, AuditId, IAV, Date)SELECT t.ComputerName, t.AuditID, t.IAV, t.DateFROM Temp t LEFT JOIN MasterList m ON m.ComputerName = t.ComputerNameWHERE m.ComputerName IS NULL; INSERT INTO MasterList(ComputerName, AuditId, IAV, Date)SELECT t.ComputerName, t.AuditID, t.IAV, t.DateFROM Temp tWHERE NOT EXISTS( SELECT * FROM MasterList m WHERE m.ComputerName = t.ComputerName);