As of August 01, 2026, the average annual salary for Senior Environmental Scientist in Illinois is $111,357, equivalent to $54 per hour, $2,141 weekly, or $9,280 monthly. These figures, sourced from Salary.com’s real-time job posting scans, highlight competitive earning potential for Senior Environmental Scientist in cities like San Jose, Santa Clara, and San Francisco.
Annually Salaries for Senior Environmental Scientist in Illinois vary widely, spanning from $95,426 to $134,463. Most professionals fall between the 25th percentile ($103,018) and 75th percentile ($123,452), while top earners (90th percentile) make $134,463 per year. This $20,434 pay gap underscores opportunities for salary growth through certifications, specialized skills like Consulting or AutoCAD, or targeting high-paying regions like District of Columbia or California.
Location and experience significantly influence earnings. For example, Illinois Senior Environmental Scientist often earn 1.9% higher than national averages due to demand from Fortune 55 companies. However, Illinois currently ranks 14 nationwide for Senior Environmental Scientist job salary. Professionals are advised to focus on high-growth sectors like to offset market challenges.
