Bulgaria's National Revenue Agency (NRA) warned 3600 that it puts them under special observation, reports Vesti.bg.

NRA sent letters to the firms that their activities and cash registers are being supervised, due to considerably lower than usual turnover, compared to similar companies. 

Among those observed are retailers, cafes, restaurants, medical practices, hairdressers and beauty parlours and parking lots. 

The tax office warned that if the low turnover continues for no apparent economic and market reasons, it will send inspectors, including mystery clients, to check if cash receipts are being issued. 

The NRA has the practice to analyse data from the more than 400 000 cash registers directly connected to the tax databases and look for discrepancies in turnovers or dubious increases in sales in the end of the day or month, when no sales were registered in the previous hours or days. 

The tax servers register the issuing of more than 400 M cash receipts each month and allow the automatic detection of considerable deviations from the average for a given sector or geographical area. 

“Those letters are a first, friendly, warning,” the director of the Control department or NRA, Vasil Panov, said. “If the companies don't get back in line and start reporting the real data, then we start the inspections and sanctions.