Choosing to retire in December 2026 or waiting until January 2027 can change both the access requirements and the amount of the pension. Next year, the schedule for the gradual increase in the standard retirement age comes to an end, and new parameters for calculating the benefit come into effect. Added to this is the annual revaluation of pensions, which must also be taken into account before deciding when to stop working.
The difference is not the same for everyone. A worker with a long contribution history may find themselves in a different situation from another who has not yet met the years needed to retire at 65. What’s more, waiting a month can improve the calculation if it allows them to add new contributions, although it can also lead to less favorable contribution bases or modify the coefficients applicable to an early retirement.
There is no general rule that allows us to say that December is better than January. Social Security has an official simulator that makes it possible to compare dates and obtain a personalized estimate of the pension.
What age you need to retire in December 2026 and January 2027
The first change affects the standard retirement age. In 2026, people may retire at 65 if they have contributed at least 38 years and three months. If they do not meet that period, the standard age is 66 years and ten months.
From January 1, 2027, ordinary retirement increases to 67 years, except for those who can prove at least 38 years and six months of contributions, who will be able to keep retiring at 65.
| Requirement | December 2026 | January 2027 |
|---|---|---|
| General standard age | 66 years and 10 months | 67 years |
| Standard age with a long contribution record | 65 years | 65 years |
| Contributions needed to retire at 65 | 38 years and 3 months | 38 years and 6 months |
This can be decisive for a person who turns 65 at the end of 2026 and already meets 38 years and three months of contributions. If they meet the requirements to retire in December, they can access ordinary retirement under the rules in effect at that time. If they decide to wait, they will have to check whether on the new date they will meet the 38 years and six months required in 2027.
The change of year does not eliminate early retirements or special schemes, which have their own requirements. It also does not mean that a person who already has their pension recognized must re-prove the required years in 2027.
How pension calculation changes in 2027
In addition to age, January introduces a change in the calculation of the regulatory base, the amount to which the corresponding percentage for the years paid is applied.
From 2026, two formulas coexist and Social Security must apply the most favorable to the pensioner during the legally provided transitional period.
The first uses the contribution bases of the last 25 years, that is, 300 months, divided by 350.
The second allows selecting the higher amount contribution bases within a broader period. Its application is progressive:
| Formula | 2026 | 2027 |
|---|---|---|
| Traditional system | Last 300 months of contributions, divided by 350 | Last 300 months of contributions, divided by 350 |
| Alternative system | 302 best bases from the last 304 months, divided by 352.33 | 304 best bases from the last 308 months, divided by 354.67 |
| Applicable criterion | The most favorable formula | The most favorable formula |
The alternative system allows discarding some of the less favorable contribution bases within the period examined. It may be useful for workers who have experienced interruptions in employment or salary reductions, although it does not guarantee an improvement for all future pensioners.
Also in 2027, the scale that determines what percentage of the regulatory base corresponds according to the years paid changes. To obtain 100% of the regulatory base, in general, 37 years of contributions will be needed, compared with the 36 years and six months required in 2026.
It is advisable not to confuse this figure with the 38 years and six months needed to retire at 65 years in 2027. One thing is the age of access and another is the percentage of the regulatory base that corresponds for the contribution record.
What happens with the increase in the January 2027 pensions
Another important element is the annual revaluation. Contributory pensions are updated, in general, according to the evolution of the consumer price index (IPC) expected in the regulations.
Anyone who retires in December 2026 and has a contributory pension recognized may benefit from the revaluation that corresponds starting in January 2027.
Meanwhile, anyone who starts receiving their pension in January 2027 will obtain an initial amount calculated using the rules and bases applicable to their retirement date. The pension already recognized is not automatically added to that new pension the revaluation percentage.
Therefore, when comparing the two dates, you have to deal with the December pension once it has been revalued, with the initial pension that would correspond in January. Comparing only the initial amounts of both months can lead to an incorrect conclusion.
The final revaluation percentage for 2027 has not yet been approved. The reference will depend on legally forecast inflation data and its subsequent official approval.
Example of a person who can retire in December or wait until January
Let’s imagine a worker who meets the requirements for ordinary retirement in December 2026 and whose simulator calculates an initial pension of 1,500 euros per month.
If they retired in December, their pension would be updated in January according to the revaluation percentage that is finally approved. If, just as an example, that increase were 2.5%, they would start receiving approximately 1,537.50 euros per month.
But if they decided to keep working until January, the Social Security would have to recalculate their pension with the new contribution bases, the calculation period, and the percentage that would apply to them. The result could be higher or lower than those 1,537.50 euros.
The 2.5% used in this example is hypothetical, not an official forecast of an increase for 2027. Without knowing the worker’s actual contributions, it is not possible to determine which option is more advantageous.
Waiting a month can change early retirement
For those who want to retire before the ordinary retirement age, the comparison requires special attention.
Voluntary early retirement generally allows the ordinary age to be brought forward by up to two years, provided that the contribution requirements and the rest of the legal conditions are met. Involuntary early retirement includes other scenarios and may allow an even greater advance.
In these cases, reducing coefficients apply that depend, among other factors, on the months of early retirement and the contribution period.
Delaying retirement from December to January can reduce the advance by one month relative to the ordinary age and change the penalty. However, the change in the legal requirements in 2027 can also affect the reference age, so it should not be assumed that waiting will always reduce the discount.
The comparison must be made with the exact dates and the retirement modality that applies.
How to know whether it suits you to retire in December or January with the official simulator
Social Security offers a free retirement simulator that uses the contribution data available in its records and allows you to enter different retirement dates.
To make the comparison:
- Access the Social Security retirement simulator and identify yourself through one of the approved systems.
- Check that your work history and contribution bases are correctly included.
- Enter a retirement date in December 2026, provided you meet the legal requirements.
- Save the report with the age at access, the regulatory base, the applied percentage, and the estimated pension.
- Repeat the simulation with a January 2027 date and review the differences.
- Compare the amounts, taking into account the January revaluation, the additional months of contributions, and, if applicable, the coefficients for early retirement.
The simulator allows you to modify certain contribution forecasts and download the results in PDF. The amounts it offers are indicative and may vary if the data or the applicable rules change.
If the tool does not yet incorporate some definitive 2027 parameter, such as the annual revaluation, the simulation will have to be reviewed when it is officially published.
What you must check before deciding the retirement date
The choice does not depend only on the monthly payment that appears in the simulator. The timing of when you stop receiving the salary and when you start receiving the pension also matters.
A person who retires in December will begin receiving the benefit before another who continues working until January. The latter, in turn, will be able to receive the salary corresponding to the additional time worked and add new contributions.
The economic comparison should take into account the total income in both scenarios, not just an isolated monthly payment. It also makes sense to review possible extra payments, the tax treatment of the income, and the effective date of access to the pension.
In short, 2027 introduces important changes to the standard retirement age, the years of contributions required, and the calculation of the pension. Retiring in December may be favorable in some cases, while waiting until January may improve the outcome in others. The way to check this is to carry out two individual simulations before communicating the retirement date.