The two men, 45 and 47, were detained in March and were charged after telephoning 137 people, 37 of whom were tricked into handing over cash and valuables believing they had been speaking with their grandchildren.
The scam earned the two fraudsters over a million kronor in cash ($148,170) and at least 215,000 kronor worth of jewellery.
The crimes were committed within a four month period, with the majority of victims being women aged over 80, the oldest being a woman born in 1912 who was tricked out of 50,000 kronor.
The case has been labelled as aggravated fraud, with the trial beginning on August 20th at the Hudiksvall District Court in eastern Sweden.
The frauds took place throughout northern and eastern Sweden, with police completing a though investigation.
“It was an extensive investigation that spanned 31 cities,” explained Lars Berglund of the Gävleborg police to the TT news agency.
The con men preyed on the weak points of the elderly victims, carefully researching them before making their pleas, often claiming that the money would go towards a new car. If the money they received was not considered satisfactory, the pair asked for watches or jewellery.
Often, it wasn’t until the victims called to ask for their money back that they realized they had been conned.