Senior Accountant, Revenue & Accounts Receivable

Sim Space serves as an AI Proving Ground where organizations can confidently train, test, and outmaneuver adversaries in any environment. Trusted by allied governments, militaries, enterprises, and research institutions worldwide, Sim Space enables adaptive, AI-ready defenses that stay ahead of evolving threats. Founded in 2015 by experts from U.S. Cyber Command and MIT Lincoln Laboratory, the platform unifies training, testing, and validation in a realistic, live-fire simulation-helping teams evaluate security investments, optimize performance, and compress cyber readiness cycles from months to days.

Why join Sim Space? We are an organization that is focused on building our culture and mindfully enhancing our atmosphere every day which is why we have collaborated on an integral value system. Our governing philosophy of being Human Centered is deeply embedded within our value system. We apply this philosophy to every one of our internal team members, external clients, and their customers.

How Do We Work? We believe that people are at the center of everything we do. Sim Space fosters a culture of continuous learning, curiosity, and professional growth. That belief shows up in action: in-house training, internal and external learning platforms, cyber conferences, industry events, and dedicated time for skill development. Our people are empowered to shape their careers - and it shows.

Year over year, Sim Space consistently outperforms industry benchmarks in internal mobility, promotions, and total rewards growth.

Who Thrives Here? We are a team of innovators, protectors, and problem-solvers. We believe diversity of thought and experience fuels better solutions, and we’re committed to building teams that reflect the communities we serve. Whether you’re remote or office-based, you’ll collaborate with talented colleagues across departments and time zones, united by the mission to create a safer digital world.

We are looking for a detail-oriented Senior Accountant – Revenue & Accounts Receivable to join our Finance & Accounting team orting to the Controller, this role will own the day-to-day revenue accounting and accounts receivable functions while supporting the monthly close and financial reporting processes.
The ideal candidate has strong experience with customer billing, revenue recognition under ASC 606, collections, and general ledger accounting. This role works closely with Sales, Customer Success, and Sales Operations to ensure accurate billing, timely cash collections, and compliance with U.S. GAAP in a fast-growing SaaS environment.

• Prepare and maintain revenue recognition schedules in accordance with ASC 606.
• Record monthly revenue recognition and deferred revenue journal entries.
• Review customer contracts to determine appropriate revenue treatment.
• Reconcile deferred revenue, contract assets, and other revenue-related balance sheet accounts.
• Partner with Sales and Customer Success to ensure customer contracts are accurately reflected in the ERP system.
• Support month-end and year-end close activities related to revenue accounting.

• Own the end-to-end customer billing process, ensuring invoices are accurate and issued timely.
• Maintain customer accounts and resolve billing discrepancies.
• Monitor accounts receivable aging and proactively manage collections.
• Communicate with customers regarding outstanding invoices and payment status.
• Research and resolve customer payment issues in partnership with Sales and Customer Success.
• Apply customer payments and reconcile customer account balances.
• Prepare bad debt reserve analyses and recommend write-offs when appropriate.
• Monitor customer credit risk and escalte collection issues as necessary.

• Prepare journal entries and maintain accurate accounting records within Net Suite.
• Perform balance sheet account reconciliations.
• Assist with treasury activities, including daily cash monitoring, application and reconciliations.
• Support accounts payable activities as needed.
• Track fixed assets and prepare depreciation entries.
• Suppo…