Accounts Payable Manager

About the role

Mariana Minerals is a software-first, vertically integrated minerals company on a mission to supply the critical minerals powering modern energy, AI, and defense technologies. We're reimagining the minerals supply chain by combining deep industry expertise with advanced software, automation, and data-driven decision-making. The Accounts Payable Manager will own the end-to-end accounts payable function for multiple entities, ensuring the accurate and timely processing of supplier invoices while enforcing strict compliance with internal controls and purchasing policies. This leader will build and scale a technology-enabled procure-to-pay operation that supports the company's rapid growth trajectory and strengthens vendor relationships. The role requires close collaboration with Procurement, Operations, Accounting, Treasury, FP&A, and business leaders across various operating locations to align on financial and operational objectives. The hire will drive continuous improvement initiatives, leverage automation opportunities, and establish robust processes that enhance efficiency, transparency, and reliability in payments.

Key facts

What you'll do

Supervise and assist in the daily processing of vendor invoices across multiple legal entities to ensure operational efficiency and accuracy.

Ensure invoices are processed accurately, completely, and in accordance with company policies and payment terms to mitigate financial risk.

Execute three-way matching of purchase orders, goods receipts, and vendor invoices to validate transactions and prevent discrepancies.

Review invoice coding for accuracy, including general ledger accounts, departments, projects, entities, and budget classes to maintain precise financial records.

Manage invoice queues and monitor service-level expectations to guarantee timely processing and adherence to internal standards.

Coordinate weekly payment proposals with Treasury to support working-capital objectives while maintaining strong vendor relationships.

Monitor accounts payable aging and proactively identify risks or issues that could impact cash flow or compliance.

Serve as the primary escalation point for vendor inquiries, account statements, and payment disputes to resolve matters efficiently.

Build and maintain strong relationships with key suppliers through consistent communication regarding payment status and terms.

Coordinate the resolution of invoice discrepancies with Procurement and operational teams to ensure data integrity and alignment.

Oversee vendor onboarding documentation, including W-9 or W-8 forms, banking information, tax forms, certificates of insurance, and other required support.

Prepare and complete vendor credit applications to establish or expand supplier credit terms and optimize cash flow.

Assist in maintaining an accurate vendor master and support vendor due-diligence processes to ensure compliance and accuracy.

Supervise, coach, mentor, and develop Accounts Payable staff to build a high-performing team aligned with company goals.

Establish performance expectations and monitor individual and team productivity, quality, and timeliness to drive accountability.

Develop cross-training plans to ensure operational continuity, knowledge sharing, and appropriate coverage across the team.

Promote a culture of customer service, accountability, collaboration, and continuous improvement within the AP function.

Identify opportunities to automate invoice processing, approval workflows, and exception handling to increase efficiency and reduce manual effort.

Support the implementation and optimization of AP automation tools, OCR technologies, and ERP workflows to enhance scalability.

Develop and maintain standard operating procedures, desk procedures, and process documentation to ensure consistency and compliance.

Ensure compliance with internal controls, segregation of duties, procurement policies, and payment authorization requirements at all times.

Support internal and external audit requests and remediation activities to maintain transparency and regulatory alignment.

Monitor key performance indicators and recommend actions to improve operational efficiency, accuracy, and team performance.

Prepare and report key Accounts Payable metrics, including invoice processing cycle time and backlog to support strategic decision-making.

Provide regular reporting and recommendations to Finance leadership on AP trends, risks, and improvements.

Requirements

Bachelor's or Associate's degree in Accounting, Finance, Business Administration, or a related field is required.

Five or more years of progressive Accounts Payable experience is mandatory, including at least two years supervising or leading AP staff.

Experience in manufacturing, mining, or industrial environments is required due to the complexity of operations and compliance needs.

Strong understanding of accounts payable processes, general ledger accounting, and financial controls is essential for success in this role.

Proficiency with ERP systems, AP automation platforms, and Microsoft Office Suite, particularly Excel, is required to manage workflows and reporting.

Ability to manage multiple priorities in a fast-paced environment while maintaining attention to detail and accuracy.

Excellent written and verbal communication skills are necessary for interacting with vendors, internal stakeholders, and cross-functional teams.

Strong problem-solving and analytical skills are required to investigate discrepancies, resolve exceptions, and improve processes.

Demonstrated ability to work independently and as part of a collaborative team in a matrixed organizational structure.

Commitment to maintaining the highest level of integrity, professionalism, and confidentiality in handling sensitive financial information.

Willingness to adhere to company policies, procedures, and regulatory requirements governing financial operations and vendor management.

Nice to have

Experience with OCR and AP automation tools such as Coupa, Bill.com, or similar platforms.

Knowledge of mining or natural resources sector financial operations and compliance standards.

Familiarity with ERP systems commonly used in manufacturing and industrial companies.

Practical notes

This role is based in Houston, TX and requires in-office presence during standard business hours.

Travel is not required for this position.

No visa sponsorship is available for this role at this time.