15 October 2026

AT/MP rate 2027: calculation at the company level becomes mandatory

What the Decree No. 2026-951 changes for multi-establishment companies

Starting with the contributions due in 2027, companies subject to individual or mixed pricing will automatically benefit from an AT/MP rate calculated at the company level, for each risk category. Until now, they could request the application of a single rate. This change may modify the rate for certain establishments and requires an analysis of the claims across the company.

What will the 2027 AT/MP rate decree change?

Decree No. 2026-951 of October 13, 2026, generalizes the calculation of the AT/MP rates at the company level for employers subject to individual or mixed pricing. It applies to contributions due starting in 2027.

In practice, the rate is calculated for each establishment or group of establishments belonging to the same risk category. The reform therefore does not necessarily mean that one company will have a single rate for all its establishments and activities combined.

How did the single rate work until now?

Until now, the AT/MP rates were generally established by institution, according to its activity and its pricing model. Multi-establishment companies with individual or mixed pricing could request a single rate for institutions belonging to the same risk category.

Starting in 2027, calculating at the company level will become the rule for the affected companies: requesting this option is no longer necessary. The accident rate of the affected establishments is thus taken into account at the company level, within their risk category.

Who is affected by the AT/MP rate calculated at the company level?

The reform concerns employers in the general scheme, excluding Alsace-Moselle, who are subject to individual or mixed pricing. It therefore primarily targets multi-establishment companies falling under these pricing schemes.

Location

What you must remember

Single-site company

There is no mutualization between institutions; the main effect of the reform concerns multi-site companies.

Collective pricing

The decree targets individual and mixed tariffs.

Multi-establishment company with individual or mixed pricing

Calcul at the company level, by risk category.

Company located in Alsace-Moselle

Out of the scope of the decree.

The mixed pricing applies to companies with 20 to 149 employees, while the individual pricing applies to those with at least 150 employees. The BTP and Alsace-Moselle regions have specific thresholds.

What will be the effect on your institutions’ rates?

The effect will depend on the severity of each establishment, its risk category and the salary mass taken into account. An establishment whose rate was lower than that of other establishments of the same category may see its rate increase; an establishment whose rate was higher may, conversely, benefit from mutualization.

The reform therefore does not allow a systematic increase in contributions for all the companies involved. A simulation based on the rates and accident data for each establishment is necessary to estimate the impact.

Which rule applies to new establishments?

The decree distinguishes between two situations:

The risk category already exists within the company: the rate determined at the company level applies to the new establishment.
The risk category is new: the net collective rates apply for the year of creation and the two following calendar years.

In other words, a new establishment that falls into a risk category already present in the company may, from its inception, be subject to the rate calculated for that category.

How is the transition to the 2027 rates calculated?

To assess the rate variations in 2027, the decree provides for a reference based on the average of the net rates reported in 2026 to institutions of the same risk category. This average is weighted by the payroll of the last year known for these institutions.

This provision frames the transition to the new calculation for 2027. It does not prejudge the evolution of the rates in subsequent years.

What can be done to anticipate the reform?

The priority is to understand how the transition to calculating by company and by risk category could affect your institutions.

Mapping establishments by risk category

This involves identifying the establishments, their risk codes, their reported rates and their payrolls. The risk category is decisive in determining which establishments are subject to the same calculation.

Simulate the impact of mutualization

It will involve comparing the current rates and the claims experience of establishments belonging to the same category. This analysis allows identifying the establishments that are likely to see their rates change and measuring the magnitude of the effect.

Strengthening the steering of prevention

With an assessment carried out at the company level based on risk categories, prevention at a single site can have effects beyond that site alone. Monitoring the frequency and severity of incidents must be part of a coordinated approach between the affected establishments.

In a nutshell

Starting in 2027, the AT/MP rate for companies with individual or mixed pricing will be determined at the company level, by risk category. The impact will depend on the insurance claims and payroll of the affected establishments. The first step is to map these establishments and simulate the effect of the new rule on the rates.

Our AT/MP experts can assist you in analyzing your data, simulating the impact, and identifying your prevention measures.

Contact our experts

Frequently Asked Questions

Does the single AT/MP rate apply to all companies?

No. The decree targets employers in the general scheme subject to individual or mixed pricing, excluding Alsace-Moselle. The calculation is carried out by risk category.

Will the AT/MP rate of each institution increase in 2027?

Not necessarily. The evolution depends on the severity of the incidents and the size of the payroll of the establishments grouped in the same risk category.

What happens when a company creates an establishment?

If the risk category already exists within the company, the calculated rate for that category applies. If it is new, the net collective rates apply during the year of creation and the following two calendar years.