The bill, passed by 48 votes to 30, is designed to curb the informal economy by making it harder for businesses to cheat on retail revenue.

The opponents from the ranks of the opposition Democratic Party (SDS) and New Slovenia (NSi) begged to differ though, arguing that the system would only bring extra costs for businesses.

The online system will send all receipts automatically to the Financial Administration (FURS) for verification prior to them being printed by businesses.

The government plans to raise an additional EUR 50-100m in VAT receipts a year. Setting up the system is expected to cost FURS around EUR 2m.

Following the test run beginning on 1 December, the system will kick in on 2 January 2016.

A two-year transition period will follow in which businesses will be able to operate with special carbon copy receipts that will then have to be verified with the revenue service within ten days.

The bill proposes stiff fines for violators, with corporations facing fines up to EUR 75,000 and sole proprietors up to EUR 25,000 for a standard violation. Fines for serious violations go up to EUR 125,000.

Individual clients failing to retain a copy of the receipt until they leave the store or as long as the warranty period is in place face a fine of up to EUR 40, down from EUR 400 initially proposed.

FURS director Jana Ahčin announced today that technical specifications for the system would be ready in August so that software makers would be able to develop solutions.

"The Financial Administration will set up a test environment for VAT-registered businesses and software developers to test their products in September," Ahčin explained.

The system will be obligatory for legal and physical persons accepting cash who are obliged to keep books of account and records with the exception of providers of basic utility services.

The legislation has been met with mixed reactions, with trade unions welcoming the idea.

While representatives of large companies support it as one of the tools for fighting grey economy, representatives of small businesses fear additional costs.

The government has estimated the cost for businesses per cash register at up to EUR 300, but the Chamber of Trade Crafts and Small Business (OZS) claims it will cost between EUR 1,500 and EUR 1,800.