In brief

• The annual rate of change for the Construction Cost Index in December 2025 was the highest since July 2024.
• The costs of electricity decreased by 7.4 percent in December compared to November 2025 but were 0.1 percent higher compared to December 2024.
• Interest costs increased by 1.3 percent in December compared to November but were 7.3 percent lower compared to December 2024.
• Construction clients’ costs decreased by 1.8 percent in December 2025 compared to December 2024.

Changes in the last month

The Construction Cost Index for multi-dwelling buildings decreased by 0.1 percent between November 2025 and December 2025. This decrease was due to the fact that the contractors’ costs decreased by 0.3 percent while the construction clients’ costs increased by 0.4 percent. These two groups account for 82 percent and 18 percent, respectively, of the Construction Cost Index.

Costs in the group ‘transport, fuel and electricity’ decreased by 2.4 percent. Within that group, the cost of electricity, diesel oil and cost of transport fell by 7.4 percent, 4.0 percent and 0.6 percent, respectively. Contractors’ overhead costs, cost of machinery and wages and salaries were unchanged or fell by up to 0.1 percent.

Contractors’ costs for building materials decreased by 0.2 percent in December 2025. Among the building material groups, the cost of concrete products and electric material fell by 0.8 percent and 0.3 percent, respectively. The remaining material costs were unchanged or increased by up to 0.2 percent between November and December 2025.

Construction clients’ costs increased by 0.4 percent in December. Construction clients’ costs consist of interest and credit costs, costs for plans, and central administration. The increase in construction clients’ costs was due to higher interest costs which rose by 1.3 percent.

Changes in the last year

The Construction Cost Index for multi-dwelling buildings increased by 1.3 percent between December 2024 and December 2025. Contractors’ costs rose by 2.1 percent, which led to an upward contribution to the Construction Cost Index of 1.7 percentage points. Construction clients’ costs decreased by 1.8 percent, which led to a downward contribution to the Construction Cost Index of 0.4 percentage points. The decreased construction clients’ costs was due to lower interest costs, which decreased by 7.3 percent. The remaining construction clients’ costs increased by between 0.5 percent and 3.7 percent.

Contractors’ costs for ‘wages and salaries’ and overhead costs increased by 3.5 percent and 2.5 percent respectively, while costs for machinery and ‘transport, fuel and electricity’ decreased by 0.1 percent between December 2024 and December 2025. Within the group of ‘transport, fuel and electricity’, the cost of diesel oil decreased by 6.2 percent. The decrease was somewhat offset by an increase in cost of transport and electricity, which increased by 0.7 percent and 0.1 percent respectively.

Contractors’ costs of building materials increased by 1.8 percent between December 2024 and December 2025. All costs in the building material groups rose except the cost of electric materials and other building materials, which both decreased. The costs of materials for painting and wood products increased the most, by 10.7 percent and 8.6 percent respectively.