Mercor is hiring a **Fractional Billing & AR Operations Specialist** on behalf of a fast-growing AI research lab. This organisation partners with enterprises, research institutions, and venture-backed startups to deliver cutting-edge AI solutions. As the company scales, they are seeking an experienced billing and accounts receivable professional with a background in **professional services environments (consulting, legal, advisory, or similar)**. This role will bring structure, accuracy, and operational rigour to client billing, collections, and revenue tracking processes. This is an ideal opportunity for a detail-oriented finance operator who thrives in high-growth environments and can build scalable billing systems while maintaining strong client communication standards.
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## Key Responsibilities
### Billing Operations
- Own end-to-end client invoicing cycles, including time-and-materials, milestone-based, and retainer billing structures
- Ensure accurate tracking of billable hours, project codes, and client-specific terms
- Partner with internal stakeholders (finance, operations, client leads) to validate invoice inputs
- Maintain clear documentation of billing policies and workflows
### Accounts Receivable (AR) Management
- Monitor outstanding invoices and proactively manage collections
- Lead professional, client-facing communication regarding billing inquiries and payment follow-ups
- Maintain AR aging reports and provide visibility into cash flow forecasts
- Identify patterns in payment delays and recommend process improvements
### Process & Systems Optimization
- Assess and improve billing systems, tools, and reporting workflows
- Implement scalable controls to support growth in client volume
- Support monthly revenue reconciliation and financial reporting
- Ensure compliance with contractual terms and internal financial controls
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## Requirements
- 5+ years of experience in billing and AR operations
- Prior experience in **professional services environments** (consulting firms, law firms, advisory practices, or similar)
- Strong understanding of:
- Time-based and project-based billing models
- Revenue recognition fundamentals
- AR aging and collections workflows
- Experience working with accounting platforms (e.g., QuickBooks, NetSuite, Xero, or similar)
- Excellent written communication skills for professional client correspondence
- High attention to detail and strong process discipline
- Ability to work independently in a fractional capacity
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## Preferred Qualifications
- Experience supporting venture-backed startups or high-growth technology companies
- Familiarity with SaaS or AI services billing structures
- Experience building billing processes from early-stage or scaling environments
- Background in financial reporting or FP&A collaboration
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## Why Join
- Work at the forefront of AI innovation
- Help operationalise finance infrastructure for a rapidly scaling AI lab
- Flexible fractional engagement with meaningful ownership
- Direct impact on revenue operations and cash flow strategy