Sr. Payroll & Benefits Specialist (4573)

Position Summary
The Senior Payroll & Benefits Specialist manages accurate, timely payroll processing and benefits administration, including U.S. multi-state payroll compliance, international payroll coordination, and Employer of Record (EOR) payroll setup and execution. As a member of the People Operations team, this role also supports payroll reporting, audits, leave administration, employee onboarding and offboarding, and other departmental projects.

Key Responsibilities

• Manage end-to-end U.S. multi-state payroll, including payroll changes, deductions, reconciliations, and coordination of federal, state, and local tax compliance.

• Coordinate international payrolls with local providers, ensuring accurate inputs, timely processing, and resolution of payroll issues.

• Set up and execute payroll through EOR partners, including employee setup, payroll approvals, funding coordination, and ongoing reconciliation.

• Administer employee benefits, including enrollments, qualifying life events, terminations, open enrollment, and payroll deductions.

• Prepare and reconcile payroll reports; partner with Finance on payroll journal entries, accruals, and related reporting.

• Support 401(k), workers’ compensation, and other payroll and benefits audits by preparing records, reconciling data, responding to requests, and resolving discrepancies.

• Coordinate leave-of-absence administration with third-party administrators (TPAs), including applications, supporting documentation, payroll and benefits adjustments, employee communications, and applicable compliance requirements.

• Support workers’ compensation administration, including applications, payroll reporting, coordination with carriers and TPAs, and related compliance documentation.

• Support onboarding and offboarding, including HRIS updates, benefits communications, and final-pay coordination.

• Maintain accurate, confidential employee records; respond to payroll and benefits inquiries; and support compliance activities, process improvements, and other People Operations projects.

Qualifications

• 5+ years of payroll and benefits administration experience, including hands-on U.S. multi-state payroll compliance.

• Experience coordinating international payrolls and implementing and processing payroll through EOR providers.

• Experience with payroll reporting, 401(k) and workers’ compensation audit support, and leave-of-absence coordination with TPAs.

• Strong payroll/HRIS systems proficiency, Excel skills, attention to detail, and ability to manage sensitive information.

• Strong communication, organizational, and problem-solving skills.

Physical and Environmental Considerations:

• Must be able to sit/stand for long periods of time.
• Required use of standard office equipment including laptop, phone, copier, etc.
• Typical office environment.
• Must be able to walk through the factory environment safely.

The hiring range represents what Mevion Medical Systems, Inc. reasonably expects to pay for this position at the time of posting. The actual salary offered will depend on the selected candidate’s qualifications, experience, skills, and other job-related factors.