Spain's tax administration (the AEAT) has announced the release of the SII 2018 deadline calculator. This tool is designed to help calculate the exact date by which each SII report should be submitted to the AEAT. Determining the exact day of the deadline can be confusing under the current system when factoring in weekends and other Spanish holidays. This tool will ensure that these dates are not taken into account when calculating the deadline, and will also help to clarify any possible confusion arising from the fact that starting January 1, 2018, the deadline for reporting inbound and outbound invoice transactions will be reduced from 8 days to 4 days.
The tool can be found here.