If you need to review your case or confirm how your medical leave is calculated from December 2026 onward, you can contact Fernanda Vargas via WhatsApp or book a consultation on Calendly.
The calculation of medical leave in Spain changes for many temporary disability cases due to common contingencies starting on December 1, 2026. The new development is not in the subsidy percentages, which remain the same, but in the regulatory base used as the reference: now, as a general rule, one more month back is taken into account. This can clearly affect those who have recently had a pay raise, receive variable pay items, or have just started working.
Chap. 1 — What Changes: RDL 31/2026 and the New Regulatory Base for Medical Leave
Royal Decree-Law 31/2026, published in the BOE on October 21, 2026 and in force from that same day, changes the way the regulatory base for temporary disability due to common contingencies is calculated. The practical idea is simple: for medical leave to which the new rule applies, the reference is no longer the month immediately before the leave begins, but instead the month immediately before the month preceding the leave.
In other words, for leave due to common illness or a non-work-related accident, the general rule is no longer to look at the last closed month before the leave starts, but the month before that one. That is why leave starting on December 15, 2026 is calculated using the contribution base for October 2026, not November.
This change may seem technical, but it has real financial effects. If salary went up recently, the benefit may continue to be calculated for one more month using an older base. And if pay has variable components, the result will depend on the specific month included in the calculation.
Chap. 2 — The New Rule Step by Step: Base for the Month Before the Month Preceding the Leave
To calculate the regulatory base for temporary disability due to common contingencies under the new rule, it is useful to follow these steps:
- Identify the exact date when the medical leave starts.
- Identify the month immediately before the month of the leave.
- Go back one more month.
- Take the contribution base for that second month.
- Divide that base by the number of days to which that contribution corresponds.
The legal reference revolves around the triggering event of the temporary disability. In practice, for most employees, this means that the relevant month is the one two months before the start of the leave.
| Leave start date | Previous month | Month used for the regulatory base |
|---|---|---|
| December 2026 | November 2026 | October 2026 |
| January 2027 | December 2026 | November 2026 |
| February 2027 | January 2027 | December 2026 |
That is why, when a company or a worker reviews leave from late 2026 or early 2027, it is not enough to look at the last payslip before the leave. You have to check which month actually enters into the formula.
Chap. 3 — Since When It Applies: Leave Starting on or After December 1, 2026 and Transitional Doubts
The general rule relevant to employees for common contingencies takes effect from December 1, 2026. That is the key date for determining whether leave falls under the new calculation system.
That said, there is a transitional point that should be followed closely. The final provision setting the effective date refers to December 1, 2026 for several amendments to the General Social Security Law, including Article 171. However, the first transitional provision refers to temporary disability processes starting from the entry into force of the royal decree-law. This creates doubts for leave starting between October 21 and November 30, 2026.
Until there is a firm interpretive clarification, the prudent approach is to treat that period as an area of possible dispute. If your leave started on those dates and the amount does not match what was expected, it is worth reviewing the calculation in detail.
Chap. 4 — Practical Examples: Leave in December, January, and February
Examples help show the real effect of the change. Below are simple cases for guidance purposes.
Example 1: leave on December 15, 2026. If the contribution base for October 2026 was 1,860 euros and corresponds to 31 days, the daily regulatory base would be 60 euros. With that base, from day 4 to day 20 the subsidy would be 60%, that is, 36 euros per day. From day 21 onward, it would be 75%, that is, 45 euros per day.
Example 2: leave on January 10, 2027. The previous month is December 2026, so the relevant month becomes November 2026. If the November base was 1,800 euros and corresponds to 30 days, the daily regulatory base would be 60 euros. The financial result by periods would be the same as in the previous example.
Example 3: leave on February 20, 2027. The previous month is January 2027, so the month entering the calculation is December 2026. If the December base was 2,170 euros and corresponds to 31 days, the daily regulatory base would be 70 euros. From day 4 to day 20, 42 euros per day would be paid, and from day 21 onward, 52.50 euros per day.
These examples show the logic of the system: what matters is not the month in which the medical leave certificate is issued, but which contribution base falls within the reference month established by law.
Chap. 5 — What Does Not Change: Unpaid Days, 60%, 75%, and Who Pays Each Period
The reform does not change the usual percentages of the temporary disability subsidy for common contingencies. The classic structure remains:
- The first three days do not generate a subsidy, unless an improvement is provided for in the collective bargaining agreement (convenio).
- From day 4 to day 20, 60% of the regulatory base is paid.
- From day 21 onward, 75% of the regulatory base is paid.
The express reference that days 4 to 15 are paid by the company also remains unchanged. Therefore, the relevant new development in December 2026 is not the percentage applied, but the regulatory base on which that percentage is calculated.
A very clear example is a daily regulatory base of 60 euros: from day 4 to day 20, 36 euros per day would be paid, and from day 21 onward, 45 euros per day. What is new is how that daily base of 60 euros is reached.
Chap. 6 — Newly Hired Workers: Starting in the Month of Leave or the Previous Month
The new Article 171.3 introduces specific rules for those who have just joined the company. They are very important because they prevent the mechanical application of a monthly reference that, in these cases, may not exist or may not reflect the real situation.
If joining took place in the month before the leave, the regulatory base is calculated using the contribution base for that previous month. In other words, you do not go back one more month.
If joining took place in the same month as the leave, the contribution bases for the days worked from registration with Social Security (alta) until the day before the leave are taken. That sum is used to calculate the regulatory base based on the days actually worked during that period.
Practical example: if a person starts work on January 3 and goes on medical leave on January 20, it would make no sense to go back to November of the previous year as if they had been with the company for months. In this special case, the relevant bases are those generated between registration and the day before the leave.
These rules matter a great deal in recent hires, seasonal campaigns, starts following a change of company, and the first weeks of employment.
Chap. 7 — Pay Raises, Variable Hours, and Working Time Changes: Who May Receive Less (or More)
One of the most discussed practical effects of the reform is that a recent pay raise may take one more month to be reflected in the temporary disability benefit.
For example, if salary increases in November 2026 and leave starts in December 2026, the new general rule points back to October 2026. This means the benefit may continue to be calculated using the previous salary during that first month of application of the new system.
Something similar happens with variable pay. If a person receives commissions, supplements, or items that change significantly from one month to another, the result will depend on the reference month included in the formula. An especially good or especially weak month may increase or reduce the daily regulatory base.
Changes in working time may also have an impact. If the change in working time is recent, it will be necessary to check whether the general rule applies or one of the special rules for recent hires. In these cases, carefully reviewing the payslip and the contribution base is essential.
The practical conclusion is clear: when there have been changes in salary or working time shortly before the leave, it is advisable to do the calculation with the dates in hand and not assume that the latest payslip will be the one that counts.
Chap. 8 — Professional Contingencies: Work Accident and Occupational Disease
The reform does not unify all temporary disability cases under the same formula. For professional contingencies —work accident and occupational disease— a separate system remains in place.
The regulatory base is still made up, on the one hand, of the contribution base for professional contingencies, excluding overtime, divided by the number of days to which that contribution corresponds; and, on the other hand, overtime from the previous year divided by 365.
Therefore, the December 2026 change affects temporary disability due to common contingencies, but does not replace the specific formula that was already being used for professional contingencies.
Chap. 9 — Self-Employed Workers: New Regulatory Base from October 21, 2026
Self-employed workers (autónomos) have their own rule. From October 21, 2026, the regulatory base for temporary disability, whatever the contingency, is the contribution base for the month immediately before the month preceding the triggering event, divided by 30.
The rule also adds that self-employed workers are not subject to the rules in sections 2 and 3 of Article 171. In other words, their calculation follows a separate path.
A simple example: if the relevant contribution base is 1,800 euros, the daily regulatory base will be 60 euros.
In addition, from January 1, 2027, the bases corresponding to periods of temporary disability and other protected situations are excluded from contribution regularization. For many self-employed workers, this makes reviewing bases and protected periods an even more relevant issue.
Chap. 10 — Checklist for Companies and HR: Payroll, Software, and Communication to Staff
For companies and human resources departments, the change requires a review of internal processes. This checklist can serve as a starting point:
- Check whether the leave arises from common or professional contingencies.
- Identify the exact start date of each temporary disability process.
- Apply, from December 1, 2026 onward, the general rule of looking at the month before the month preceding the leave, where applicable.
- Detect cases where joining took place in the previous month or in the same month as the leave.
- Check that the payroll program and management software are configured with the new time reference.
- Keep the subsidy percentages for common contingencies unchanged: 60% from day 4 to day 20 and 75% from day 21 onward.
- Inform staff that a recent pay raise may not be immediately reflected in the benefit.
- Closely monitor leave starting between October 21 and November 30, 2026, because of the existing transitional doubt.
- Keep a traceable record of the calculation applied in case of later review.
In practice, many errors will come more from old automatisms in the payroll system than from not knowing the rule. That is why it is advisable to review the parameters before the first December leave cases start to come in.
Chap. 11 — Special Attention to Foreign Workers: First Weeks of Employment and Renewals
For many foreign workers, this reform is especially important. It is common for medical leave to coincide with the first weeks in a new company, a recent job change, or a delicate moment in their work history in Spain. In those cases, the special rules for joining in the previous month or in the same month as the leave may be decisive.
It is also worth paying attention to employment and contribution documentation when the situation coincides with residence procedures or renewal applications. A correct temporary disability calculation does not replace those procedures, but it can prevent mistakes at a time when every payslip and every Social Security registration counts.
If you need help reviewing a leave, a payslip, or an issue with Social Security (Seguridad Social), you can use Fernanda Vargas’s employment law and Social Security service. Fernanda Vargas can also coordinate the employment side with the immigration situation when both issues overlap.
In addition, the same royal decree-law creates special temporary disability situations for secondary menopausal disorder and for injuries resulting from gender-based violence, with no minimum contribution period and payment from the day after the leave begins. These are specific cases that deserve separate review.
Chap. 12 — Frequently Asked Questions and What Is Still Pending (Validation in Congress)
There is one final point that should not be overlooked: since this is a royal decree-law, it must be validated by Congress within 30 days in accordance with Article 86 of the Constitution. Therefore, the rule is in force, but its parliamentary path matters. It would not be the first time that a measure of this kind required adjustments or new rules after the validation debate.
Is my leave starting on November 30, 2026 already calculated under the new rule?
This is a case with transitional doubts. The general effective-date rule points to December 1, 2026, but the transitional provision of the royal decree-law has created doubts for processes starting between October 21 and November 30, 2026. If your leave falls within that interval, the specific calculation should be reviewed.
If my salary was increased in November and I go on leave in December, will I be paid based on the new salary?
Not necessarily. If the new general rule applies and the leave starts in December 2026, the reference month will be October 2026. That may mean the November increase is not yet included in the regulatory base calculation.
Are the first three days of leave paid?
As a general rule, there is no subsidy for the first three days of leave due to common contingencies, unless an improvement is provided for in the collective bargaining agreement. From day 4 to day 20, 60% of the regulatory base is paid, and from day 21 onward, 75%.
Does this reform also change leave for a work accident or occupational disease?
Not in the same way. Professional contingencies keep their own regulatory base system: contribution base for professional contingencies excluding overtime divided by the corresponding days, plus overtime from the previous year divided by 365.
What happens if I was hired in the month of the leave or in the previous month?
There are special rules. If you joined in the month before the leave, the base for that month is used. If you joined in the same month as the leave, the bases for the days worked from registration with Social Security until the day before the leave are taken.
Does the rule for self-employed workers take effect from December 2026?
No. For self-employed workers, the new regulatory base for temporary disability applies from October 21, 2026. The reference is the contribution base for the month immediately before the month preceding the triggering event, divided by 30.
Is the rule already final?
It is in force, but it must be validated by Congress within the constitutional time limit. That is why it is advisable to follow its legislative processing, especially if your case falls within the transitional period or if you are going to challenge a calculation.
If you want Fernanda Vargas to review your medical leave, your payslip, or a temporary disability case with employment or immigration impact, you can write to her via WhatsApp or book an appointment on Calendly.