Job Details: Job Location: Brea - BREA, CA, Salary Range: $20.00 - $27.50Hourly, We are seeking a detail-oriented and organized Overpayment Refund Specialist to join our ambulance billing team. This role is responsible for identifying, validating, disputing when appropriate, and processing overpayment refunds to insurance carriers, government payers, and patients while ensuring compliance with federal, state, and payer-specific regulations.   Schedule: This is an in-office position with day, swing and night shifts available.    Key Responsibilities Identify and research overpayments from Medicare, Medicaid, commercial insurers, and private pay patients Validate overpayment amounts and determine appropriate refund or dispute actions Prepare and submit disputes or appeals for incorrect or duplicate overpayment demands Review payer recoupment requests and correspondence to determine validity Process approved refunds accurately and in a timely manner, including documentation and tracking Communicate with insurance carriers, patients, and internal teams regarding refund and dispute status Monitor dispute outcomes and follow up to ensure timely resolution Ensure compliance with CMS, state regulations, and payer-specific refund and dispute timelines Maintain accurate records and audit trails for all refunds and disputes Collaborate with billing, compliance, and collections teams to prevent future overpayments Assist with internal and external audits related to overpayments, refunds, and disputes Prepare reports on refund and dispute trends, volumes, and root causes Qualifications: High school diploma or GED required 2–3 years of experience in healthcare billing, refunds, disputes, or revenue cycle management Ambulance billing experience strongly preferred Knowledge of Medicare, Medicaid, and commercial insurance billing guidelines Familiarity with HIPAA and healthcare compliance standards Strong attention to detail and accuracy Understanding of EOBs, ERAs, recoupments, and payer correspondence Proficiency with billing systems and Microsoft Office (Excel, Word) Excellent written and verbal communication skills