Construction weighs far more here than elsewhere in the Paris region. At the end of 2024, Essonne had 36,080 employer establishments, 25,159 of them with one to nine employees (69.7%, against 70.6% for the region). Construction accounts for 5,743 of them, 15.9% of establishments, against 10.7% across the Paris region; 4,165 of these have one to nine employees. It employs 39,359 people, 8.0% of salaried jobs in the département, against 5.4% for the region. Industry also counts for more: 9.1% of salaried jobs, against 6.9% in the Paris region, with a little over half (56%) in establishments of 100 or more employees.

| Area | Employer establishments, end of 2024 | Share with 1 to 9 employees | Construction's share of establishments | Construction's share of salaried jobs | Industry's share of salaried jobs |
|---|---|---|---|---|---|
| Essonne | 36,080 | 69.7% | 15.9% | 8.0% | 9.1% |
| Paris region (Île-de-France) | 497,800 | 70.6% | 10.7% | 5.4% | 6.9% |
Source: INSEE (French national statistics office), complete file for Essonne and complete file for Île-de-France, tables RES T1 and RES T2, published 27/08/2026, read 12/11/2026.
On the company side, construction accounts for 11,644 of the 94,601 businesses active in 2024, or 12.3%, against 7.9% for the Paris region; professional, scientific and technical activities and business support services account for 20.5%, against 27.9% for the region (same source, table DEN T3). The département brings together the Saclay plateau and its research labs, the business parks of Évry-Courcouronnes, Massy and Courtabœuf, and a majority of small firms in construction, retail and services. This page is written for them.

