From January 1, 2018, new proposals will come into effect with regard to the Self-Employed. You may find this interest if you are thinking of setting up a business in Spain, especially if moving here to set up a new business.
There is an obligation to pay Social Security contributions in Spain (which cover sickness, pensions etc), and the new measures include that the flat rate of 50€ per month for the first six months will now be extended to 12 months for new self-employed. Social Security is like the National Insurance system in the UK or social insurance in Ireland.
It used to be that to qualify for this you could not have been an Autonomo for the past five years, but now it is reduced to only two years since you have last been registered.
Autonomos can register and deregister now from Social Security (i.e. take a break) up to three times in a year and you only pay for the days registered in the month (as opposed to all month previously), plus they can change their contribution base up to four times a year.
After the initial twelve months, there will be a 50% reduction to 137€ for months 13-18, and then after that a 30% reduction to 192€ for months 18 -24. So it is not until after two years of working and making contributions that the new self-employed would need to pay the usual level of around 275€ per month. This gives someone a much better chance of getting a new business established and is much fairer.
Further details are contained in this document here … https://www.citizensadvice.org.es/wp-content/uploads/NEW-AUTONOMO-SELF-EMPLOYED-LAW-2017-2018-A-SUMMARY-10.pdf
It appears that this is a good new law with a lot more flexibility and long overdue.