Accounts Payable Supervisor

At MacDonald‑Miller Facility Solutions (“MacMiller”) we make buildings work better. As the Northwest’s leading mechanical contracting firm we design, deliver and service HVAC, plumbing and automation system solutions for commercial buildings. With over 1,600 employees across 14 offices, we offer a breadth and variety of work that keeps teams engaged and inspired. Our Core Culture Values—Collaboration, Dedication, Safety, Community, Innovation, and Fun—guide everything we do.

Role Overview

We are seeking an Accounts Payable Supervisor to lead our Accounts Payable team. The role ensures invoices are processed accurately and timely, vendor relationships are managed effectively, and AP processes evolve as the business grows. You will be both a hands‑on leader and a systems problem‑solver, managing day‑to‑day AP operations while identifying opportunities to improve workflows, leverage technology, and optimize operations.

Key Responsibilities

• Lead, mentor, and develop the AP team while establishing clear expectations, priorities, and accountability.
• Ensure accurate and timely processing of vendor invoices, payment requests, and related transactions.
• Continuously evaluate AP workflows and implement improvements that increase efficiency, accuracy, visibility, and scalability.
• Partner with Accounting, Procurement, Operations, IT, and other internal teams to resolve issues and improve financial processes.
• Run and support the monthly A/P close to the general ledger, ensuring accuracy and timely completion.
• Maintain strong vendor relationships and resolve invoice, payment, and account issues quickly and professionally.
• Maintain accurate AP records, monitor key metrics, and ensure appropriate processes and controls are followed.
• Develop team members and serve as a go‑to resource for AP processes.

Qualifications

• Strong leadership and management skills with the ability to mentor, develop, and motivate team members.
• 5+ years of Accounts Payable or related accounting experience; supervisory or team‑leadership experience preferred.
• Experience with corporate credit‑card platforms and employee expense reimbursement, and a strong interest in optimizing system processes.
• Experience in manufacturing, distribution, or a similar industry preferred.
• Comprehensive understanding of the full AP cycle, including invoice workflows, vendor management, and month‑end close.
• Bachelor’s degree in Accounting, Finance, Business Administration, or equivalent experience preferred.
• Strong analytical, organizational, and problem‑solving skills.
• Comfort leveraging AI and automation tools to improve AP processes.
• Ability to balance people leadership, daily execution, and systems/process improvement.

Compensation

$85,000 – $95,000 annually

Benefits

• Medical, dental, and vision coverage for employees (coverage available for dependents for shared premium)
• 401(k) retirement plan with company matching
• Vacation, sick compensation (PTO) and holiday pay
• Short‑term and long‑term disability income protection
• Employee and dependent life insurance
• Wellness program
• Employee Assistance Program

Location

Our Seattle headquarters at 17930 International Blvd, SeaTac, WA 98188 offers easy access to SeaTac International Airport, ample secured parking, newly renovated office facilities, an onsite deli, nearby restaurants, and convenient freeway/airport access.