Office Administrator

Position & Office Overview

As an Office Administrator, you are an invaluable asset who is critical to the success of the organization. The office runs like a well‑oiled machine because of your hard work and efforts. Technology is second nature to you – you are comfortable using computers and other office equipment to complete administrative and human resources‑related tasks. Maintaining a relationship with our employees and clients is a breeze because of your exceptional ability to communicate.

You are extremely dependable and put your best effort into all responsibilities. You get the “big” picture and want to contribute accordingly – and that’s why you’ll have all the opportunity for career growth within our company you’ll want.

• Perform accounting, human resources and other administrative duties with supervision.
• Process payroll, accounts payable, accounts receivable and invoicing.
• Track and document the petty cash/corporate credit card accounts by writing checks, requesting replenishments, reconciling bank and internal accounting balances.
• Process new hire, job changes, pay rate changes, and terminations.
• Complete various human resource related forms, such as employment verification paperwork.
• Track immigration status and update I‑9s as required.
• Process benefits (including new enrollments, open enrollment and update as required).
• Assist with warning reports.
• Process leave of absence and short‑term disability claims.
• Assist with other HR issues as needed.
• Maintain and update certificates of insurance.
• Enter vendor invoices into the accounting system accurately and timely.
• Reconcile vendor statements and resolve discrepancies.
• Generate and send invoices to customers in accordance with contract terms.
• Monitor outstanding invoices and ensure accurate records are maintained.
• Follow up on past‑due accounts via phone and email.
• Work with customers to resolve billing issues.
• Maintain accurate records of collection efforts and provide reports on aging receivables.
• Oversee building and equipment maintenance.
• Responsible for computer network support.
• Support receptionists and administrative management of the office.
• Other duties as assigned.

• High school diploma or GED. Bachelor’s degree (HR related) preferred.
• Minimum 2 years of experience of HR and payroll experience with an HR degree
  • 4 years of HR and payroll experience without an HR degree.

The expected pay range for this role and location is $27–$33/hour. The final agreed‑upon compensation will be determined based on specific location and other individual qualifications.

ECS Group of Companies (ECS) was founded in 1988 with the goal to raise the standards of professional engineering consulting. Today, we are a leader in geotechnical, construction materials, environmental and facilities consulting services. We are employee‑owned with more than 3,000 employees in 100+ offices and testing facilities coast to coast. ECS is currently ranked #66 in Engineering News‑Record’s Top 500 Design Firms (April 2025), #148 in Engineering News‑Record’s Top 200 Environmental Firms (October 2025) and #50 in Zweig Group’s Hot Firm List (May 2025).

For additional information about ECS, visit:

ECS is an Equal Opportunity Employer. To learn more, .