Stillwater Sciences is looking for an experienced Senior Payroll Specialist to join our Financial Accounting team. In this role, you'll lead accurate, timely, and compliant multi-state payroll processing for approximately 150 employees across seven states while supporting payroll taxes, reconciliations, reporting, and internal controls. If you bring deep payroll expertise, strong attention to detail, and a commitment to operational excellence, please apply! This is a full-time, exempt, 40 hours/week position based out of our Berkeley or Sacramento office, with a preference for Berkeley. What You'll Do Own full-cycle, multi-state payroll processing for exempt and non-exempt employees. Ensure payroll accuracy, compliance, and timely tax filings across jurisdictions. Reconcile payroll-related accounts, deductions, and benefits information. Support audits, reporting, and month-end and year-end payroll activities. Help strengthen payroll systems, documentation, and internal processes. What You'll Bring 10+ years of payroll experience, including at least 5 years with California payroll requirements. Strong knowledge of multi-state payroll, payroll taxes, wage and hour laws, and reconciliations. High attention to detail, sound judgment, and discretion with confidential information. Experience with payroll systems and reporting tools; ADP and Deltek Vantagepoint experience is a plus. Experience with project/job costing and prevailing wage is a plus. CPP certification and experience in consulting or professional services are preferred. Location and work schedule: This role is based out of Berkeley or Sacramento (preference for regular work out of our Berkeley office) and requires 5 days per week office-based work. This role is eligible for a hybrid schedule after 6 months. Compensation and Benefits For the full-time exempt Payroll Specialist position, we anticipate the range to have an annual base pay of $85,000-$105,000. Pay within this range isdeterminedin good faith and based on a combination of factors, which may include relevant education, qualifications, certifications, experience, skills, performance expectations, shift and travel requirements, and business or organizational needs. For candidates who meet the stated qualifications and experience, Stillwater typically targets pay near the midpoint of the range, recognizing that individual placement may vary. We offer a comprehensive benefits package forbenefit eligibleemployees, which includes paid time off; health, dental, life, and disability insurance; paid family leave; paid professional development; a 401(k) with employer match; and participation in our Employee Stock Ownership Program (upon meeting eligibility requirements). Stillwater covers 100% of employee medical, dental, life, and disability insurance premiums and 40% of dependent premiums. Employment Type: Full Time Years Experience: 5 - 10 years Salary: $85,000 - $105,000 Annual Bonus/Commission: Yes