Senior Accounts Receivable Associate

Trillium Professional is now seeking a Senior Accounts Receivable Associate in Irvine, CA!

We are seeking a detail-oriented and customer-focused Senior Associate, Accounts Receivable to support general AR operations and help ensure accurate, timely, and efficient processing of customer payments and account activity. This role will assist with payment application, account reconciliation, customer inquiries, collections follow-up, and resolution of payment discrepancies. The position requires strong attention to detail, effective communication, and the ability to work cross-functionally to support cash flow, maintain accurate customer accounts, and deliver a positive customer experience.

Pay rate is $25-30/hour.

• Research and resolve payment discrepancies, unapplied cash, short payments, over payments, and other account variances.
• Perform account reconciliations to ensure customer balances are accurate and properly reflected in AR systems.
• Support billing, invoice review, and customer account maintenance activities to promote accurate and timely collections.
• Communicate with internal teams and customers to address inquiries, resolve issues, and support a positive customer experience.
• Assist with collections follow-up, aging review, and escalation of outstanding balances as needed.
• Prepare and maintain AR reports, documentation, and process updates to support month‑end close and operational visibility.
• Identify process improvement opportunities to increase efficiency, reduce manual work, and strengthen controls within AR operations.

• Strong attention to detail and a commitment to accuracy in customer accounts, payment application, reconciliations, and reporting.
• Ability to research and resolve account discrepancies, unapplied cash, and customer payment issues in a timely manner.
• Clear and professional communication skills when working with customers, internal teams, and cross-functional partners.
• Strong organizational skills with the ability to manage multiple priorities, meet deadlines, and support month‑end close activities.
• A proactive, problem‑solving mindset with a focus on improving processes, reducing manual work, and strengthening AR controls.
• Comfort working with AR systems, customer account data, aging reports, and related financial information.

• 3–5 years of experience in Accounts Receivable, cash application, billing support, collections, account reconciliation, or a related finance function.
• Proficiency working with ERP, accounting, or AR systems to research customer accounts, process transactions, and maintain accurate records.
• Strong Excel skills, including the ability to analyze account activity, reconcile data, and prepare reports using tools such as Pivot Tables and lookup formulas.
• Solid understanding of AR processes, including payment application, customer account maintenance, aging review, and discrepancy resolution.
• Strong communication, problem-solving, and organizational skills with the ability to work independently, manage priorities, and meet deadlines.

Trillium is an Equal Opportunity Employer.