The Copper Theft Barometer decreased for the first time last month since February, the SA Chamber of Commerce and Industry (Sacci) said on Thursday.
Copper theft decreased to R12.2 million in June compared to R15.4m in May.
This equated to 166 metric tons of stolen copper in June, from 214 metric tons in May.
"It is too early as yet to determine whether the decline is a temporary dip in the recent upward trend, or possibly a positive indication of a downward trend reset," it said in a statement.
The barometer had previously shown three consecutive months of theft increases.
At the time Sacci called for a specialised copper theft unit.
"The outlook for copper theft levels for 2014 remains concerning despite the decrease in June," Sacci stated.
"As noted previously, a dedicated national copper theft police unit can play an important role in prosecuting larger criminal syndicates."