BT01 Index – National Building Index (all trades)

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The BT01 Index is France’s national construction index (all trades).

It measures changes in the cost of factors of production in the building industry and is the official reference for updating and revising construction contract prices.

The Index was created by a decree published in the Official Journal on December 20, 2014 (base 100 = 2010 average) and is published monthly by INSEE. It thus succeeds the Index of Building and Public Works (bases 1974 and 1975), which has been discontinued.

BT01: latest index years values
Download the latest official values of the BT01 Index

BT01 Index History

Below are the values of the Index by year with the changes compared to the previous month, the beginning of the year, over 12 months, and over 24 months:

Use of the BT01 Index:

Rule:

The price of the contract of services will be revised at each expiry of the agreement according to a formula that integrates the evolution of the BT01 Index.

Formula:

[New price] = [old price] X [Known reference index BT01] / [Reference index BT01]

Attention, do not confuse the BT01 Index with the “Construction Index” or the “Rent Reference Index” used to revise rents for private individuals and leases for professionals.

Latest BT01 Index Updates:

Latest values ​​of the building index BT01 – All trades – Base 2010:

Frequently Asked Questions about the BT01 Index

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Pascal FROMAGER

With more than 25 years of experience navigating the financial, HR, and tax challenges businesses face, I bring a wealth of practical insight to every topic. As a former Chief Financial Officer (CFO) and a graduate of the University of Rennes, I established Juristique to share this expertise in business law. My commitment is to provide ongoing regulatory monitoring and to transform complex administrative publications into clear, precise, and practical resources for readers. All content is rooted in rigorous analysis of official texts and institutional sources, ensuring reliable and regularly updated information.
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