Senior Payroll and Benefits Specialist
Allen Control Systems • Austin, Texas • Full Time
Posted on Thu, May 14, 2026
Company Overview
Allen Control Systems (ACS) is a cutting-edge defense startup founded by two former Navy electrical engineers with a proven track record in robotics and software. We are developing an autonomous gun turret using advanced computer vision and control systems to precisely detect, track, and neutralize enemy drones.
With an engineering-first culture, ACS values technical excellence and innovation. Backed by our founders’ successful exits from two previous ventures acquired for a combined $180M in 2022, we are committed to ensuring that the groundbreaking technologies we develop will have a real-world impact.
About The Role
We are looking for a Senior Payroll and Benefits Specialist to own all aspects of payroll operations and benefits administration during a critical growth phase. You will be the payroll and benefits subject matter expert for the organization, advising HR and Finance on payroll strategy, benefits optimization, and operational efficiency. This is a hands-on, detail-oriented role that combines technical payroll expertise with strategic benefits administration and process improvement across multiple states and locations.
What You’ll Do
Process bi-weekly and semi-monthly payroll across multiple states with 100% accuracy and on-time delivery; manage all payroll deductions including taxes, health insurance, 401k, HSA, FSA, garnishments, and voluntary deductions; coordinate quarterly and annual tax filings (941, 940, W-2, 1099, state/local).
Own benefits strategy and operations across health insurance, 401k, HSA, FSA, life insurance, disability, and EAP; manage vendor relationships, open enrollment, life events, and terminations; reconcile benefits invoices and conduct employee benefits education including new hire orientation and open enrollment communications.
Stay current on federal, state, and local tax law changes; ensure compliance with ACA, COBRA, HIPAA, FLSA, and wage-and-hour regulations; manage payroll audit support and maintain employment eligibility (I-9) documentation.
Own payroll and benefits systems administration; manage integrations with HRIS, benefits platforms, accounting, time tracking, and equity systems; document processes and SOPs; build dashboards tracking accuracy, processing time, benefits costs, and utilization.
Respond to employee payroll and benefits questions with professionalism and accuracy; coordinate payroll and benefits onboarding and offboarding; support compensation planning and equity management; provide payroll and benefits reporting to Finance for accounting, budgeting, and strategic planning.
What You’ll Need
7+ years of payroll and benefits experience, including at least 3 years in a senior or specialist role managing both functions.
Expertise in payroll tax compliance (federal, state, local) and strong benefits administration knowledge across health insurance, 401k, HSA, FSA, COBRA, and ACA.
Proficiency with modern payroll systems such as ADP, Workday, or Gusto; strong knowledge of multi-state payroll, particularly TX and CA.
High attention to detail, strong organizational skills, and ability to manage multiple deadlines including bi-weekly payroll cycles, quarterly tax filings, and open enrollment.
Strong communication skills and ability to explain complex payroll and benefits concepts to non-specialists; ability to maintain confidentiality and handle sensitive employee information with professionalism.
You’ll Stand Out
Payroll Compliance Specialist (PCS), Certified Payroll Professional (CPP), or Certified Employee Benefits Specialist (CEBS) certification.
Experience at a startup or high-growth company scaling from 50 to 500+ employees.
Experience with equity management, stock options, and option pool administration.
Familiarity with HRIS systems and integrated payroll, HR, and benefits system architecture.
What We Offer
Competitive salary
ACS Equity Package
Health, Dental, Vision Insurance
Paid Time Off
Allen Control Systems is an Equal Opportunity Employer, providing equal employment opportunities to all employees and applicants for employment. Allen Control Systems prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws.