Senior Accounting Manager

About Mozilla.org Mozilla is a mission-driven portfolio of companies and organizations working together to shape an internet that serves people and the public good. Currently, this portfolio includes: the Mozilla Foundation, which champions our mission through philanthropic risk capital; Mozilla Corporation, which makes Firefox; MZLA, which makes Thunderbird; Mozilla Ventures, which invests in responsible tech startups; Mozilla.ai, which creates open source AI developer tools; Mozilla Data Collective, a data sharing platform for human agency and fair value exchange. It also includes a handful of smaller strategic investments and Mozilla’s investment reserve. Mozilla.org serves as a steward of this portfolio, managing Mozilla's assets and investments to ensure they are used to advance the vision outlined in the Mozilla Manifesto. In this role, it shapes long term strategy, allocates funding and manages Mozilla’s brands. Ultimately, its job is to enable the success of all of Mozilla’s organizations in the pursuit of the overall nonprofit mission. Over the coming years, our ambition is to actively grow the portfolio—helping existing organizations grow and mature while creating or investing in new organizations that can extend Mozilla’s reach and build long-term financial value. About the Role The Senior Accounting Manager is a key member of the Finance team responsible for the integrity, accuracy, and scalability of accounting and financial operations across Mozilla.org and related subsidiaries. Reporting to the Head of Finance, this role owns multi-entity accounting, financial close and reporting, treasury, tax coordination, audit management, and financial controls. The managed entities include one non-profit organization and two for-profit organizations, one of which is international. This is a hands-on role requiring strong non-profit and for-profit technical accounting expertise, sound judgment, and the ability to operate effectively across entities with different accounting, tax, regulatory, and reporting requirements. The Senior Accounting Manager will also help strengthen the systems, processes, and controls needed to support Mozilla.org as it grows. Key Responsibilities Accounting Operations, Close & Financial Reporting Own the daily accounting in the general ledger for the three managed entities, recording transactions in an accurate and timely manner, including journal entries, expenses, accruals, pre-paids, fixed assets, inter-company transactions, revenues, and other necessary entries. Own the monthly, quarterly, and annual close processes across the entities, ensuring accurate and timely financial reporting. Maintain the integrity of the general ledger and shared chart of accounts. Partner with the Head of Human Resources to ensure the accuracy of financial information in the payroll and benefits payment processes. Prepare financial statements, management reporting, and supporting schedules Own inter-company accounting and reconciliations, including shared expenses, management fees, loans, reimbursements, and elimination entries where applicable. Ensure appropriate accounting treatment across both for-profit and nonprofit entities, including grants, functional expenses, investments, fixed assets, allocations, and other transactions as applicable. Support annual budgeting, forecasting, and financial reporting for Finance leadership and governance groups. Treasury, Tax & Compliance Oversee cash management and treasury activities, including cash flow forecasting, banking relationships, account administration, and appropriate payment controls. Coordinate federal, state, and local tax compliance across entities in partnership with external tax advisors, including corporate income tax, Form 990, information returns, and other applicable filings. Maintain visibility into filing requirements, deadlines, registrations, and potential tax or compliance exposures across jurisdictions. Ensure appropriate legal-entity separation and financial documentation across the portfolio. Audit, Controls & Financial Operations Serve as a key point of contact for external auditors and tax advisors. Coordinate audit planning and preparation of audit schedules, information requests, and supporting documentation for the consolidating audit. Respond to auditor requests and questions in partnership with appropriate internal stakeholders. Track and resolve audit findings and recommendations. Maintain and strengthen internal controls over accounting, cash, payments, banking, payroll accounting, and financial reporting and develop and maintain accounting policies, procedures, and documentation that support consistent practices across entities. Oversee accounting platforms for accounts payable, receivables, payroll, benefits, and other financial operations, ensuring accurate reconciliation to the general ledger. Identify and implement opportunities to improve, automate, and scale recurring accounting, reconciliation, reporting, and