The Social Security will modify starting next 1 December the system used to calculate temporary disability benefits. The reform changes the contribution period that serves to determine the regulatory base, a reference that directly influences the amount a person receives during a medical leave.
In the case of a full-time worker who starts a leave in December, the calculation will be made using the contribution base for October. Instead of using an average of two months, the contribution for a single monthly period will be used.
The modification is set out in Royal Decree-law 31/2026, of 20 October, which amends article 171 of the General Social Security Law. The rule also includes particularities for workers with part-time contracts, fixed-discontinuous workers, self-employed workers, and those who join a company recently.
What base will be used depending on the type of worker
For full-time workers in the General Regime, the regulatory base is obtained by dividing the corresponding contribution base for the reference period by the number of days to which that contribution corresponds. When the person receives a monthly remuneration and has been registered for the entire natural month, the divisor will be 30.
In part-time contracts and fixed-discontinuous workers, the specific method provided in article 248 of the General Social Security Law is maintained. In these cases, the bases credited since the last registration are taken into account, with a limit of the three immediately preceding months to the month prior to the event giving rise to entitlement. The result is divided by the natural days included in the corresponding period.
Self-employed workers also have their own rule. Their regulatory base will be calculated, regardless of the contingency, from the contribution base corresponding to the month immediately prior to the month before the leave, divided by 30. The law establishes exceptions for those who have been registered in the scheme in the same month or the previous month to the temporary disability.
What happens if the worker has just joined the company
The reform contemplates two situations for those who have been in their position for a short time. If the joining took place during the month prior to the start of the leave, the contribution base for that period will be used, divided by the number of days to which it corresponds.
When the registration at the company and the medical discharge occur within the same month, the corresponding contributions shall be computed for the time elapsed from the date of entry until the day prior to the temporary disability. The resulting amount shall be divided by the days included in that interval.
The new formula does not necessarily mean getting less
The economic effect will depend on the evolution of each worker’s contributions. If the base for the period now taken as reference is lower than the one used previously, the benefit may be reduced. If it is higher, the amount may increase.
The reform modifies the calculation of the regulatory base, but not the general percentages of the temporary disability benefit. In discharges due to common illness or non-work-related accident, 60% of the regulatory base is applied between the fourth and the twentieth day, and 75% from day 21 onward. In work accidents and occupational diseases, the subsidy is equivalent to 75% from the day following the day of the discharge.
What happens with discharges started before December
The new system will be applied to the temporary disability processes that begin from 1 December 2026. According to the update of the calculation manual of the Tesorería General de la Seguridad Social, discharges prior to that date will continue under the previous criterion.
The update of that manual also adapts the automatic calculation of benefits to the different contracting modalities and to the new legal rules. Its application affects the management procedures that companies and mutual insurers use to determine the regulatory bases and the amounts that must be paid.