HR/Payroll Specialist with ADP Experience

Payroll SpecialistThe Payroll Specialist owns full-service payroll operations for Collegiate Charter School of Lowell (CCSL), a K–12 Commonwealth Charter School serving approximately 1,200 students and 240 staff. This is a senior individual-contributor role responsible for end-to-end payroll administration in ADP, general ledger and accounts payable work in QuickBooks, and all reporting and reconciliation with the Massachusetts Teachers' Retirement System (MTRS). CCSL is looking for an experienced payroll professional who can operate with minimal oversight, serve as the technical authority on payroll compliance, and partner directly with the Business Office and HR on budget, audit, and year-end close.Key ResponsibilitiesOwn end-to-end payroll processing for approximately 240 staff via ADP — new hires, terminations, leave, stipends, overtime, retro pay, and off-cycle runs — with minimal supervision.Serve as the school's technical lead on ADP configuration, pay policies, deduction codes, and system troubleshooting.Own monthly MTRS (Massachusetts Teachers' Retirement System) reporting and contribution submission end-to-end; reconcile remittances against payroll deductions and resolve discrepancies directly with MTRS.Administer non-certified staff retirement contributions and coordinate with the applicable MA retirement/pension system.Reconcile payroll registers against budgeted positions and the CCSL salary scale; independently investigate and resolve variances before they reach the Business Office.Own payroll-related general ledger reconciliations in QuickBooks (payroll clearing, accrued liabilities, benefits withholdings) each month, and support broader AP/GL entries and month-end/year-end close.Lead preparation of quarterly and annual payroll tax filings (941s, W-2s) and serve as the primary payroll contact for auditors.Process and track garnishments, levies, benefit deductions, and other third-party payroll liabilities.Act as the senior point of contact for staff on pay, deductions, and MTRS/retirement questions, exercising discretion with sensitive compensation data.Partner with the Director of Finance & Director of Human Resources on annual budget development, audit prep, and Uniform Financial Statement (UFR/EOY) reporting.Maintain organized, audit-ready payroll and accounting files in compliance with state public records and retention requirements.Recommend and help implement process improvements as CCSL's payroll volume and complexity grow.Required QualificationsAssociate's or Bachelor's degree in Accounting, Business, or related field preferred; equivalent experience considered.Minimum 5+ years of full-cycle payroll experience, including ownership of compliance and reconciliation, not just data entry; school district or charter school experience strongly preferred.Deep, hands-on expertise with ADP payroll platforms (e.g., ADP Workforce Now) required — including configuration and troubleshooting, not just processing.Strong working proficiency with QuickBooks (Online or Desktop) required.Direct experience with Massachusetts Teachers' Retirement System (MTRS) reporting and contribution processes strongly preferred.Certified Payroll Professional (CPP) or Fundamental Payroll Certification (FPC) a plus.Advanced Excel skills (VLOOKUP, pivot tables, complex reconciliations).Demonstrated ability to operate independently, manage competing fiscal-year deadlines, and serve as the go-to payroll expert in a school business office.Experience with PowerSchool or similar SIS a plus.Work EnvironmentThis position is based on-site at CCSL's central administrative offices in Lowell, MA, with standard business-office hours aligned to the school's 12-month calendar. Some flexibility around payroll processing deadlines and fiscal year-end close may require adjusted hours.