Accounting Assistant

What You Will Do

The Controller Division at Los Alamos National Laboratory (LANL) provides trusted financial services that support national security and the Laboratory's mission. We offer efficient, transparent financial solutions across areas such as accounting, compliance, payroll, benefits, institutional tax, retirement, travel, disbursements, financial reporting, corporate accounting, and business systems. Our specialized groups ensure operational excellence and financial accountability. Driven by integrity, innovation, and collaboration, we continuously strive for world‑class financial operations that align with LANL's broader goals.

Join us in shaping the future of financial management and supporting our scientific and security missions.

The Controller Division is seeking to hire a highly motivated, energetic, and customer‑focused Accounting Assistant 4 to join the Accounts Payable and Disbursements Group supporting the Vendor Master File Team. The Accounts Payable and Disbursements group supports LANL's multi‑billion vendor payment operation, ensuring accurate, compliant, and timely processing of financial obligations. The group maintains financial controls through invoice validation, tax compliance, vendor master integrity, and audit preparedness while supporting a diverse supplier base and internal stakeholders.

The selected candidate will report to the Vendor Master File Manager and will provide support to the mission of the group by performing detailed invoice validation across 2‑, 3‑, and 4‑way match transactions to prevent duplicate payments, overcharges, and fraud. This position may be rotated across functional teams within the group or division to support operational needs and perform other related duties as assigned within the same job level.

This position requires the selected candidate to be onsite at Management's request and/or as needed.

• Oversees vendor onboarding, profile updates, and validations in accordance with federal and institutional compliance requirements.
• Maintains accurate and complete vendor records, including IRS documentation (W‑9/W‑8), OFAC screening, and entity classifications.
• Partners with Accounts Payable, Procurement, and Compliance to maintain a centralized, secure, and audit‑ready supplier database.
• Supports tax compliance and audit readiness through documentation standards, periodic vendor file reviews, and timely resolution tracking.
• Verifies cost allocations, purchase order accuracy, and approval hierarchies to ensure alignment with financial policies and contract terms.
• Collaborates with buyers, cost account managers, and vendors to resolve invoice discrepancies, match exceptions, and processing bottlenecks.

• Knowledge and experience in accounting principles, accounts payable bookkeeping or similar. Experience working with a large organization.

• Experience or ability to learn and use the various financial software programs and Enterprise Resource Planning (ERP). Intermediate or advanced working knowledge of Microsoft Office Suite.

• Proven strong customer service and interpersonal skills with the ability to interact with all levels of employees, vendors and management. Ability to communicate effectively both orally and in writing.

• Knowledge and experience researching, gathering, analyzing data, summarizing results, resolving problems and issues both independently and as a team member.

• Demonstrated experience organizing and prioritizing tasks with the ability to work effectively under pressure with frequent interruptions and changing priorities. Proven record of high productivity, accuracy and attention to detail.

• Excellent organizational skills with the ability to independently manage priorities and projects.
• Strong interpersonal, verbal, and written communication skills, with experience presenting complex financial data in an understandable way.
• Proven ability to work under strict deadlines, adapt to shifting priorities, and maintain accuracy and accountability.
• Demonstrated…