Fractional Billing & Accounts Receivable (AR) Operations Specialist

Remote · Part-time · Mid-Senior Level

🌍 Remote Part-time Mid-Senior Finance & Accounting
About This Role
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.

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

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

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

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

Interview Prep Guide

EXCLUSIVE

Many top hiring platforms use AI-powered screening as the first step. Here's how to stand out when applying for a Fractional Billing & Accounts Receivable (AR) Operations Specialist role:

Analytical Depth: Be ready to walk through a financial model or analysis you've built. Discuss your assumptions, sensitivity analysis, and how you handle uncertainty.

Compliance Knowledge: Discuss your familiarity with relevant standards (GAAP, IFRS, SOX) and how you ensure accuracy in financial reporting.

Business Acumen: Show how you connect financial data to business decisions — variance analysis, forecasting, and strategic recommendations.

Practice Behavioral Question

"Walk me through a project where you had to learn a new domain quickly. How did you ramp up, and what would you do differently?"