Information supplied by Citizens Advice Bureau Spain. 
For 2018
As established by Real Decreto 1077/2017 of the 29th of December – effective as of January 1st 2018:
24,53 euros/day, 735,90 euros/month (14 payments/year), 10.302,60 euros/year.
Absolute minimum wage for ´on call´ or temporary contracts (up to 120 days) of 34,85 euros a day.
Hourly wage for ´empleados de hogar´/ domestic staff in the home 5,76 euros.
For 2019
An increase of 5% and for 2020 of 10% has been established, provided that the economy grows with at least 2,5% every year and provided that each year at least 450.000 more people sign up to pay Seguridad Social contributions.
The complete document and more very useful information on all subjects of interest can be found on the CAB website here
