The JC 124 indexation in January 2027 falls on 1 January 2027: the minimum wages of construction workers rise with the average of the smoothed health index of October and November 2026, divided by that of July and August 2026. Construction indexes every quarter, so January is one of four steps. The percentage can already be calculated once Statbel publishes the November index on 27 November 2026. Below you read how the quarterly index works, what happens to higher wages and how large the steps were in recent years.
The percentage of the JC 124 indexation in January 2027
Until then there is no official percentage. The JC 124 page in the minimum wage database with the January 2026 index was last edited on 19 January 2026. Constructiv, the construction sector's joint fund, does not publish the percentage.
Federal Planning Bureau forecast. In its inflation forecasts of 6 October 2026 the Planning Bureau estimates the smoothed health index at 101.78 points in October 2026 and 102.35 points in November 2026. That is an estimate of the index, not a percentage for JC 124. The Planning Bureau does not calculate a sector percentage, and neither do we: the percentage only follows from Statbel's final figures. The next forecasts are published on 3 November 2026.
How does the indexation work in JC 124?
The rule is in the collective agreement of 12 June 2014 on the sector pay scales, which applies for an indefinite period. The minimum wages follow the health index every quarter. The percentage is the ratio of the average of the first two months of the last quarter, divided by the average of the first two months of the quarter before:
| Indexation on | Numerator: average of | Denominator: average of |
|---|---|---|
| 1 January | October and November | July and August |
| 1 April | January and February | October and November |
| 1 July | April and May | January and February |
| 1 October | July and August | April and May |
The collective agreement works with the four-month index figures, the series Statbel publishes as the smoothed health index. You round the new hourly wage to 3 decimals: if the fourth decimal is 4 or less, the third stays unchanged; if it is 5 or more, the third goes up by one.
A higher wage gets an amount. The sector only indexes the minimum wages by the percentage. If you pay more, you add the quarterly adjustment of the minimum to the wage you actually pay. For JC 124 the FPS database states: "only the minimum wages are indexed."
A negative result is not applied, but offset against the next quarter.
JC 124 indexation history since 2023
This is how the minimum wages in construction rose on 1 January in recent years, and per quarter in 2026, according to the history in the FPS minimum wage database. The sector publishes the percentage to six or seven decimals:
| Indexation on | Percentage |
|---|---|
| 1 October 2026 | 0.83% |
| 1 July 2026 | 1.10% |
| 1 April 2026 | 0.87% |
| 1 January 2026 | 0.22% |
| 1 January 2025 | 0.62% |
| 1 January 2024 | 0.45% |
| 1 January 2023 | 3.33% |
A January step in construction is small, because it only absorbs one quarter of price movement. For a full year, you add the four steps together. For January 2021 and 2022 the JC 124 history gives no usable January percentage.
What is already fixed for January 2027, and what is not?
What is already fixed:
- The date: 1 January 2027, followed by the steps of April, July and October 2027.
- The formula: the average of October and November 2026 against that of July and August 2026.
- Who gets the rise: the minimum wages by the percentage, higher wages by the same amount.
- The cents index: in JC 124 it has been running since July 2026, see below.
What is not fixed yet:
- The percentage. It follows from the November 2026 index, published on 27 November 2026.
- The new minimum hourly wages per category.
The cents index in the JC 124 indexation of January 2027
In construction the cents index does not bite for the first time in January. The first indexation after its start on 1 June 2026 was that of 1 July 2026, with 1.10%, followed by 0.83% on 1 October 2026. Together that is less than the 2% that, for a full-time reference wage above € 4,000 a month, only counts on € 4,000. Under the cents index rule, the moderation continues until the indexations together reach 2%. For anyone earning above € 4,000, part of the index therefore still only counts on € 4,000 in January 2027. For an hourly wage, you first work out the full-time monthly wage. Anyone earning € 4,000 or less gets the full index.
Meanwhile you pay a special wage moderation contribution to the NSSO. How to calculate it, with a full example, is in our piece on the cents index.
Worked example: how the January 2026 index worked
A minimum hourly wage stood at € 17.500 an hour at the end of 2025. On 1 January 2026 it rose by 0.22%: 17.50 x 1.002185875 = 17.53825, rounded to three decimals € 17.538. That is € 0.038 an hour extra. A construction worker in that category earning € 19.000 got the same amount added: € 19.038 an hour. In January 2027 it works the same way with the new percentage.
Where do you find the percentage for January 2027?
You find the percentage and the new amounts in these places:
- Statbel publishes the November 2026 index figure on 27 November 2026. With it, the formula of the collective agreement can be filled in completely.
- FPS Employment puts the percentage and the new amounts in the minimum wage database. The page with the January 2026 index was last edited on 19 January 2026.
You then also see the new pay scales on our page with the JC 124 pay scale. The committee's standing rules, the pay scales and the bonuses are in our guide to joint committee 124. What a pay rise yields net for your employee is in our guide gross to net. How the 2026 index turned out per sector is in our news on wage indexation in 2026.
What Business Centrum does for you
Business Centrum applies the January 2027 indexation in JC 124 in your payroll administration, together with Acerta, with the percentage that follows from the collective agreement. We apply each quarterly index to the minimum wages, add the same amount to higher wages and follow the cents index per employee. All committees that index in January, with their formula, are in our overview of the January 2027 indexation.