Part-Time Payroll, Accounts Payable, and Office Administration

PHNX Materials Inc.; San Leandro (CA); On-site; USD 32,000 - 47,000; Part time

Job summary

PHNX Materials Inc. is seeking a part-time Payroll & Office Administrator to manage payroll, keep books, and support daily office operations. You’ll ensure accurate payroll processing, maintain QuickBooks records, and handle vendor payments and invoicing with careful attention to detail.

The role requires you to work 20-25 hours weekly, with one in-office day each week. Candidates should be organized, reliable, and comfortable coordinating multiple office tasks on-site in San Leandro, California.

Qualifications

• Experience with payroll processing and accurate time record verification.
• Proficient in QuickBooks and handling vendor payments.
• Ability to submit invoices to third parties and maintain organized records.

Responsibilities

• Process payroll accurately and on time, verify records and changes.
• Review payroll reports, resolve discrepancies, obtain approvals.
• Maintain QuickBooks entries and confidential payroll records.
• Process vendor invoices and track payment deadlines.
• Coordinate payroll and benefits systems; manage invoicing workflow.
• Receive and route checks, bills, and mail; maintain office records.
• Coordinate janitorial and office supplies; manage routine needs.
• Escalate missing information to prevent missed deadlines.
• Maintain checklists to ensure recurring tasks are completed.

Skills

Payroll processing

QuickBooks

Vendor payments

Invoice processing

Attention to detail

Organizational skills

Tools

QuickBooks

Spreadsheets

Job description

This is a part-time role, 20-25 hours per week, with one flexible day per week on site.

About PHNX

PHNX Materials is the world’s first solids’ refinery company. We extract 30+ critical metals from industrial waste while selling 100% of the input feed as co-products. We are unlocking America's domestic supply of critical minerals.

About The Role

PHNX Materials is seeking a part-time Payroll & Office Administrator to manage payroll and keep essential office operations running smoothly. You’ll own accurate, timely payroll processing, maintain records in QuickBooks, coordinate office services, and ensure incoming checks, bills, and requests reach the right people. This role requires exceptional attention to detail, sound judgment, and consistent follow-through. You’ll work 20-25 hours per week, including one day in the office each week; the on-site day is flexible, with availability around payroll deadlines required.

What You’ll Do

• Process payroll accurately and on time, verifying time records, pay rates, deductions, and employee changes before submission
• Review payroll reports, resolve discrepancies, and obtain required approvals before processing
• Maintain accurate QuickBooks entries and organized, confidential payroll and financial records
• Process and pay vendor invoices with appropriate approvals, tracking due dates and payment confirmations
• Manage internal Payroll and Benefits management system
• Prepare and submit invoices to third parties for payment, maintain supporting documentation, and follow up on outstanding balances
• Receive, log, and route incoming checks, bills, and mail
• Coordinate janitorial services, office supplies, and other routine office needs
• Route questions and documents to the appropriate person and follow through until resolved
• Escalate missing information, discrepancies, and time-sensitive issues early enough to prevent missed deadlines
• Maintain clear checklists and records so recurring tasks are completed reliably

What We’re Looking For

• Hands-on experience with payroll, QuickBooks, vendor payments, and submitting invoices to third parties for payment
• Exceptional attention to detail, with a demonstrated record of payroll accuracy and careful verification
• Strong organization, discretion, and follow-through; sound judgment about routing information and escalating issues
• Ability to work independently within a part-time schedule, meet payroll deadlines, and work on site one flexible day per week

Nice to Have

• Experience supporting a manufacturing, industrial, or plant-based business
• Experience coordinating janitorial services and other office vendors
• Comfort with spreadsheets and improving administrative checklists and processes
• Experience working with an external accountant, bookkeeper, or payroll provider