The mandatory nation-wide rollout follows a one-month trial period in which only some 15% of the 70,000 businesses and individuals required to use fiscal registers took part.

Between the evening of 31 December 2015 and Saturday morning, the digital certificate without which certified cash registers do not work was acquired by almost 1,000 new taxpayers.

Today, on the first day of the mandatory use, around 150 new taxpayers entered the system each hour, the Financial Administration (FURS) told the STA. It expects that the acquisition of digital certificates will continue in this pace on Sunday.

By 3 PM today a total of 36,497 businesses and individuals have acquired the certificate, while certified cash registers are being used only by 19,807.

The new system is designed to curb tax evasion and has been mulled by several governments before being adopted by the Miro Cerar government and passed in parliament in the summer of 2015.

The system connects cash registers directly with the central IT system of FURS, where the receipts are confirmed before they are printed out.

Each receipt gets a unique identifier making it possible for tax inspectors to verify whether the proceeds have been reported.

As a result, the government expects between EUR 50m and 100m more in tax receipts a year.

FURS will also be able to establish potential violations related to undeclared work as the receipt also contains information on the physical person issuing it.

The system is mandatory for businesses that are required to issue receipts for goods and services and to keep accounting ledgers and records, and that accept cash, which also includes credit and pay cards.

Those who only issue a small number of receipts will be able to verify them via a free application called Mini Register accessible on the FURS web site.

They will be able to continue to issue carbon receipts if they opt for a two-year transitional period, but only if they do not have an electronic device they can issue receipts on the premises with.

As of 2018 only those that can prove they do not have an internet connection will be able to continue to operate with pre-numbered receipt books.

All taxable persons are required to post standardised notices informing their customers that they will be issued a receipt which they must keep when leaving the premises.

Unless they do so they are liable to a fine of between 2,000 and 50,000 euros.

A fine is also envisaged for the customer who fails to take a receipt, but FURS says it will check the latter as a preventive measure. Customers will also be encouraged to take a receipt with a lucky draw.

According to FURS, inspectors are already checking the use of certified cash registers. Those who do not commit severe or repeated violations will only be warned at first.

Once the system is fully implemented, the administration expect several million of receipts to be confirmed every day. It confirmed a total of 1.1 million receipts by 3 PM today.