Senior Manager, Accounting & Finance

Why Thunderbird?

Thunderbird is one of the world’s most trusted open-source email applications, empowering more than 20 million people globally. At Thunderbird, we build privacy-respecting communication and productivity tools that help people manage their digital lives while staying in control of their data.

We are open source by design. Our products are developed transparently and in collaboration with a global community of contributors, and that same spirit shapes how we work: collaboratively, inclusively, and with a shared commitment to putting users first.

We are a small but growing company of 70+ people distributed across seven countries. As Thunderbird evolves beyond a single desktop application, we are expanding across desktop, mobile, paid services, and new product experiences that help people and organizations work more effectively without giving up control to big tech ecosystems.

Our revenue model combines user donations, which help keep Thunderbird’s apps freely available, with paid services that cover the costs of hosted offerings while supporting long-term sustainability and continued innovation.

A note about Thunderbird and Mozilla: Thunderbird Technologies Corporation is the nonprofit-owned company behind Thunderbird email and a growing portfolio of products. While part of the Mozilla family, Thunderbird is a separate entity from Mozilla Corporation and Mozilla Foundation with its own compensation programs, benefits, and employment policies.

To learn more, visit www.thunderbird.net

The opportunity

We are looking for a Senior Manager, Accounting & Finance to serve as Thunderbird’s most senior finance professional. The right person will bring a strong accounting or controllership foundation and the breadth to lead financial planning and analysis, finance operations, and organization-level decision support.

As Thunderbird grows across donations, subscription services, enterprise offerings, and international operations, our financial needs are becoming more complex. We need stronger integration across accounting and FP&A, experienced oversight of emerging revenue models and tax obligations, and clear financial analysis that helps leadership understand performance, risks, tradeoffs, and decisions.

Reporting to the Chief Operating Officer, the Head of Finance will directly manage our Senior Staff Accountant and Senior FP&A Analyst. This is a hands-on functional leadership role for someone who can provide experienced financial judgment, develop an established team, and remain close to the details while helping build the systems, controls, reporting, and finance practices the organization needs for its next stage of growth.

This role requires regular working-hour overlap with the COO, finance team, and other colleagues across North American time zones. Candidates based in Eastern or Central time zones are preferred; candidates elsewhere in the United States should be comfortable maintaining substantial overlap with those working hours. Flexibility for meetings with colleagues, advisers, and affiliated organizations in Europe is also expected.

What you’ll do 

• Lead Thunderbird’s finance function, with overall responsibility for accounting, financial planning and analysis, tax, treasury, and finance operations.
• Manage and develop Thunderbird’s finance team, establishing clear priorities, responsibilities, review practices, and accountability.
• Oversee monthly and annual close, financial reporting, reconciliations, accounting policies, and internal controls.
• Oversee accounting and revenue recognition across donations, subscriptions, enterprise arrangements, partnerships, and other revenue streams.
• Lead annual budgeting, forecasting, longer-range financial planning, and scenario analysis.
• Develop clear management reporting and visualizations that highlight important trends, risks, tradeoffs, and decisions.
• Oversee tax, audit, indirect tax, VAT/GST, corporate filings, and related work with external advisers.
• Evaluate the financial, tax, accounting, and operational implications of entering new jurisdictions or establishing additional entities.
• Work with Enterprise Partnerships and Legal to establish financial reporting, reconciliation, and control processes for partner-led commercial arrangements.
• Oversee financial reporting to Thunderbird’s parent organization and affiliated Mozilla organizations.
• Own financial oversight of payroll across multiple providers in partnership with the People team.
• Document and strengthen finance systems and workflows, including accounting, expense management, payment-platform reconciliation, documentation, and automation.
• Oversee cash-flow planning, treasury, banking, and investment activities, working closely with the Senior FP&A Analyst.
• Serve as a trusted finance adviser to organizational leaders, translating complex financial information into clear recommendations.

What you bring 

• 15+ years of relevant professional experience, including progressively responsible roles spanning accounting, financial planning and analysis, and finance operations.
• Significant accounting or controllership experience, including responsibility for U.S. GAAP financial reporting, close processes, internal controls, revenue recognition, and complex accounting judgments.
• 5+ years of people management experience in a finance or accounting environment, including coaching, feedback, prioritization, performance support, career development, and team development.
• Demonstrated ability to improve budgeting, forecasting, management reporting, and financial data visualization and translate complex information into clear insights and recommendations for non-finance leaders.
• Substantive experience with subscription, SaaS, digital-product, enterprise, or comparable technology-based revenue models.
• Experience supporting partner-led commercial arrangements, such as reseller, licensing, wholesale, or revenue-sharing models, including evaluating financial terms and developing or overseeing the related reporting, reconciliation, controls, and revenue-recognition processes.
• Working knowledge of merchant-of-record arrangements, payment platforms, indirect tax, and international VAT/GST requirements.
• Experience supporting an internationally distributed organization and coordinating financial obligations across multiple jurisdictions.
• Proven ability to oversee tax, audit, and other external finance requirements and effectively manage outside advisers.
• Experience providing oversight and review of cash management, treasury, banking, and organizational investment activities, including developing recommendations for senior decision-makers.
• A track record of strengthening financial systems, workflows, documentation, and controls.
• Strong judgment and comfort moving between people leadership, detailed financial review, practical hands-on problem-solving, and organization-level decision support.
• Excellent communication and cross-functional collaboration skills, including the a