US Tax Senior Manager

Location: Hybrid / Mayfair, London, UK
job type: Permanent / Full-time
Sector and subsector: Accounting & Finance | Audit & Practice
Salary: Negotiable salary

About us

Big decisions deserve clear thinking.

At Sopher + Co, we've spent more than 50 years helping entrepreneurs and high-net-worth individuals navigate complex financial and commercial challenges. From tax planning and private office services to business advisory and technology, we bring everything together to make life simpler and help our clients focus on what matters most.

We don't just solve problems. We build relationships, offer clarity, and give our clients the confidence to move forward. And it's our people who make that possible.

We started in Elstree in 1975, working closely with clients in the media, entertainment and music industries. Today, we support a diverse and prestigious client base across more than 20 sectors, with a continued strong and long-standing presence in entertainment and media. While we've grown, our approach hasn't changed. We keep things straightforward and focus on advice that is practical, personal, and easy to act on.

If something's complex, we simplify it. That's where we add value.

The role

We're looking for an experienced UK-US Tax Senior Manager to join our specialist US/UK tax team in our Mayfair office.

This is a senior, client-facing role. You'll run a portfolio of US-connected individuals, families and trusts, and own both their UK and US personal tax affairs. Your clients include US citizens and green card holders living in the UK, UK residents with US income or assets, internationally mobile executives, entrepreneurs, and clients from our long-standing entertainment and media base with earnings in both countries.

You'll run your portfolio through managers, act as the primary day-to-day adviser to your clients, and turn compliance relationships into advisory work. You'll also play an important part in the continued growth of this specialist service line.

Other responsibilities include, but are not limited to:

Compliance and advisory

• Sign off complex UK Self Assessment returns, US Forms 1040 and 1040-, and related US information returns across your portfolio.
• Advise on pre-arrival and departure planning, including the Statutory Residence Test, the four-year foreign income and gains (FIG) regime and UK inheritance tax under the long-term residence rules.
• Advise on the UK and US tax treatment of trusts, including US reporting of non-US trusts and their US beneficiaries.
• Integrate UK and US analysis across compliance, transactions and planning, for example on a business sale, share awards or a family succession event.
• Lead the response to HMRC and IRS enquiries, and coordinate UK and US input.

Financial and commercial

• Own the financial performance of your portfolio, including WIP, billing, recoveries, aged debt and profitability.
• Scope, price and resource engagements, and act on underperforming work.
• Expand existing relationships and maintain a pipeline of opportunities.
• Support proposals, fee discussions and business development led by Directors and Partners.

People and team

• Manage, coach and develop managers and their teams towards autonomy and future leadership.
• Own engagement resourcing and give your team broad UK-US experience.
• Act as a role model for Sopher + Co's technical, commercial and client-service standards.

Client and relationship

• Act as the primary day-to-day adviser to your clients and build trust with their lawyers, wealth managers and family offices.
• Explain complex matters clearly and resolve client issues before they need senior escalation.
• Introduce specialist colleagues where your clients need wider support.
• Own risk across your portfolio and set consistent review and documentation standards for your teams.
• Manage regulatory and reputational risk, including client acceptance and continuance.
• Decide when to elevate material exposure to a Director or Partner.
• Improve how your portfolio is delivered through technology and standardisation.
• Transfer knowledge and remove single points of failure in delivery.

What you'll bring

You're a recognised technical authority across UK and US personal tax, and confident without relying on jargon. You build trust by making complex cross-border matters easy to understand.

You're commercially minded. You understand how your portfolio makes money and act early when it falls short.

You lead people well. Your managers come to you for judgement, not instruction.

You communicate clearly and professionally, and…