Tax Manager/Senior Tax Manager

Old Mission is a global proprietary trading firm that leverages state-of-the-art technology and research to identify and execute profitable trading strategies across multiple asset classes around the world. Our offices in Chicago, New York, and London are all composed of naturally-curious individuals who thrive in a team environment and constantly strive for improvement.

Old Mission does not seek capital from outside investors, allowing us the flexibility to aggressively invest in our team members and keep them engaged in the firm’s growth.

About the position

This is a hands-on role in every sense. The Tax Manager works alongside the Tax Director, not behind them. Both positions are expected to work together: preparing workpapers, reviewing returns, conducting primary research, owning compliance deadlines, and building the analysis that informs the firm’s tax positions.

Responsibilities

U.S. International Tax

Prepare and own U.S. international tax compliance workpapers and supporting schedules across the firm's controlled foreign corporations and partnerships, including GILTI/NCTI, FDII/FDDEI, BEAT, Subpart F, foreign tax credits and FTC limitation analysis, and foreign withholding and treaty positions

Maintain and update CFC and partnership analyses including tested income, tested loss, net deemed tangible income return calculations, and high-tax exclusion evaluations; coordinate with external advisors on FTC planning and transfer pricing strategies

Monitor the impact of OBBBA, evolving IRS guidance, and OECD Pillar Two developments on the firm's international tax positions and assess implications for compliance and planning

Support transfer pricing documentation and intercompany agreements for cross-border transactions between U.S. and foreign entities.

Federal, State Local Tax Compliance

Prepare tax return information packages and detailed workpapers for external tax consulting firms; independently review all externally prepared federal and state returns prior to submission

Support preparation and review of indirect tax filings including VAT, Use Tax, and GST across applicable domestic and international jurisdictions

Own withholding and information reporting obligations for Forms 1099, 1042-S, and 8804 for the firm and its related entities

Build and maintain the firm’s tax compliance calendar; proactively identify all upcoming deadlines and coordinate timely completion with internal teams and outside advisors

Research, Planning Authority Response

Conduct primary research on federal, state and local, and international tax issues; prepare well-reasoned technical memos for Tax Director review

Prepare substantive responses to information document requests (IDRs) from the IRS, state, and city taxing authorities; maintain organized examination support files

Monitor and assess legislative and regulatory developments including IRS guidance, Treasury regulations, and OECD Pillar Two updates; brief the Tax Director on implications for the firm

Provide tax analysis in support of proposed transactions, new entity structures, and strategic initiatives

Process, Data Technology

Identify and implement process improvements to tax workflows; evaluate new tools and procedures for more accurate, efficient compliance

Leverage Excel (Power Query, XLOOKUP, PivotTables, array formulas) and AI research tools to streamline workpaper preparation, data manipulation, and reconciliation

Document and maintain policies, procedures, and internal controls for the Tax function

Work cross-functionally with Accounting, Legal, and Operations on tax matters, regulatory reporting, and ad hoc special projects as directed

Required Skills

6–8+ years of tax experience; public accounting background at the Manager or experienced Senior level strongly preferred (Big 4, national firm, or strong regional with FS practice)

Genuine hands-on technical depth in U.S. and international tax, direct experience preparing and reviewing GILTI/NCTI, Subpart F, and foreign tax credit workpapers; conceptual familiarity alone will not meet the bar

Experience preparing and independently reviewing federal and state tax returns and workpapers, preferably in a financial services, partnership, or trading firm context

Working knowledge of indirect tax, VAT, Use Tax, or GST in a compliance setting

CPA licensed or within one exam section of completion (active license strongly preferred)

Advanced Excel proficiency, XLOOKUP, PivotTables, Power Query, SUMIF/SUMIFS; comfort manipulating large financial datasets

Exceptional attention to detail and organizational discipline; able to manage multiple high-stakes deadlines without dropping the ball

Impeccable ethics, integrity, and proven ability to handle confidential and market-sensitive information

Preferred Skills

Prior experience in a financial services tax environment, proprietary trading firm, hedge fund, or investment partnership

Transfer pricing experience, including intercompany agreemen…