It comes after the deputy Prime Minister, Pablo Iglesias, confirmed in December that the governing coalition would look into the proposals made by the leftwing party, Más País.
The pilot will go ahead despite opposition from some leaders, who called the idea a “madness” in the wake of the country’s economic difficulties last year.
A study conducted by Trades Union Congress in 2019 also found that those in countries with shorter working weeks are more productive.
Employees in Denmark, which has the shortest working week in Europe, are 23.5 per cent more productive than they are in the UK, the research suggested.
While the exact details of the pilot are being discussed, Más País has proposed a three-year €50m (£30.77m) project that could allow companies to trial reduced hours with minimal risk, the Guardian reported.
It would also see companies trial the scheme with costs covered at 100 per cent for the first year, falling to 50 per cent for the second year and 33 per cent for the third, it added.
Héctor Tejero of Más País expects the pilot to begin as early as autumn.
But a source with Spain’s industry ministry said talks over the pilot project were in their initial stages, the Guardian reported, adding that at this period in time everything is still up for debate.