Since 2025, regulatory pressure has intensified for the tertiary sector in France. All companies occupying premises larger than 1,000 m² are now required to demonstrate their energy compliance or face financial penalties and negative publicity. Far from being a mere administrative constraint, this obligation represents a major strategic opportunity to optimize your consumption and sustainably reduce your energy costs. This comprehensive guide, designed by EnergyProMag.com experts, provides you with the methodology and tools to transform this requirement into a performance lever for your business. The Eco-Energy Tertiary scheme (DEET), better known as the Tertiary Decree, is at the heart of France’s energy transition strategy. It imposes a drastic reduction in energy consumption for the entire tertiary building stock. The stakes are high, the penalties dissuasive, and the deadline for declaring 2024 data is set for September 30, 2025. To help you see clearly and act effectively, we have developed a complete compliance checklist accompanied by infographics and summary tables. Table of ContentsWhat is the Tertiary Decree? An Obligation to Transform into an OpportunityOrigin and Ambitious ObjectivesWho is Affected by this Regulation?The 3 Fundamental Pillars of the ObligationTertiary Decree Obligations in 2025: Deadlines and Performance LevelsKey Deadlines from 2025 to 2050Absolute Value vs. Relative Value: Which Method to Choose?Data to Provide on the OPERAT PlatformThe OPERAT Platform: Your Step-by-Step DeclarationTertiary Decree 2025 Compliance ChecklistPenalties for Non-Compliance: What Real Risks?The 3-Step Penalty ProcessIndirect and Collateral RisksThe 3 Most Common Mistakes to AvoidAid and Subsidies: How to Finance Your Compliance?Energy Savings Certificates (CEE): The Main LeverADEME and BPI France AidRegional and Local AidHow to Effectively Reduce Your Consumption and Achieve Objectives?Energy Audit: The Mandatory Starting PointPriority Action Plan: Prioritize to OptimizeAnnual Monitoring: Measure to ManageFAQ: Tertiary Decree 2025 – Your Questions, Our AnswersWhat exactly is the Tertiary Decree?Who must declare on the OPERAT platform?What buildings are covered by the Tertiary Decree?How to calculate the reference consumption?What are the penalties for forgetting or non-compliance?What’s the difference between absolute value and relative value?What tools to use to monitor compliance?Does the Tertiary Decree concern rented buildings?What is the deadline for the 2025 declaration?How to prove compliance...