Senior Payroll Accountant

At Slingshot Aerospace, we're on a mission to make space safer and more secure for everyone. Our work directly impacts global security, disaster response, climate monitoring, and the critical infrastructure that connects our world. We're a team of builders, thinkers, and problem-solvers who believe that the next generation of space operations will be powered by better data and smarter software. We move fast, we're not afraid to fail, and we believe the best ideas can come from anywhere—whether you're in engineering, sales, product, or operations. If you want to work on something that truly matters, with people who care deeply about the impact we're making and help shape the future of an industry that's just getting started, you're in the right place.

The Payroll Accountant will ensure accurate and timely payroll processing across U.S. and U.K. operations while maintaining compliance with all applicable tax regulations and statutory requirements. This role is critical in supporting accounting operations through payroll reconciliations, reporting, and audit readiness, while partnering cross-functionally to ensure data accuracy and process efficiency.

We're building a team of sharp, creative people who love solving hard problems. We value curiosity over ego, initiative over waiting for permission, and people who genuinely care about doing great work. Bring your expertise, your fresh ideas, and your drive—we'll bring the rocket fuel.

• Process bi-weekly, semi-monthly, and monthly payroll accurately and on schedule for U.S. and U.K. employees
• Ensure compliance with federal, state, local, and UK payroll tax regulations, including withholding, unemployment, and statutory requirements
• Prepare, review, and file payroll-related tax forms (e.g., W-2, W-3, quarterly payroll tax returns)
• Ensure compliance with UK statutory payroll requirements
• Reconcile payroll-related accounts, including wages, taxes, deductions, and benefits
• Manage payroll accounting activities, including journal entries, account reconciliations, reporting, and month-end close processes
• Support review and posting of timesheet submissions in partnership with Program Finance
• Lead annual 401(k) audits and prepare and file Form 5500
• Support worker’s compensation policy renewals and lead annual audits
• Manage quarter-end and year-end payroll close processes, including accruals, schedules, tax filings, and audit documentation
• Monitor payroll tax law changes and update internal processes to ensure compliance
• Respond to employee payroll inquiries and provide timely, high-quality support
• Partner with Human Resources and Accounting teams to ensure accurate payroll data and employee records
• Support payroll system enhancements, testing, and configuration updates to improve accuracy and efficiency
• Participate in process improvements, automation initiatives, and cross-functional projects
• Maintain strict confidentiality of payroll and employee data in accordance with company policies and applicable regulations, including GDPR

• Bachelor’s degree in Accounting, Finance, or related field
• 3–5 years of experience in payroll accounting, payroll tax, or related function
• Strong understanding of payroll tax regulations across federal, state, and local jurisdictions
• Experience with multi-state payroll
• Familiarity with UK payroll compliance requirements
• Experience with payroll systems (Rippling and Tilt preferred)
• Proficiency with ERP/accounting systems (e.g., NetSuite, Deltek Costpoint)
• Understanding of U.S. GAAP principles
• Advanced Excel skills preferred
• Strong analytical skills and attention to detail
• Excellent communication and organizational skills
• Ability to manage deadlines in a fast-paced environment

• Experience supporting audits (401(k), worker’s compensation, or payroll-related audits)
• Experience with payroll process improvements or system implementations
• Familiarity with automation tools or payroll system integrations