Boston-based tax lawyers McMahon & Associates represent businesses with Internal Revenue Service (IRS) and state tax controversies, including:

  • Audits and examinations
  • Collections
  • Voluntary disclosure
  • Appeals

  • Litigation
  • Foreign bank accounts
  • FBAR requirements

Experienced IRS Tax Attorneys

Collectively, our team of attorneys and enrolled agents has more than 100 years of experience investigating and defending IRS and state tax matters. All of our senior attorneys and enrolled agents are former IRS Attorneys, IRS Appeals Officers or Revenue Agents.  That means we know exactly what is involved in a tax audit, appeal or litigation and how best to negotiate with the IRS.

Our tax attorneys have had distinguished careers in the Boston and Massachusetts IRS offices:

  • D. Sean McMahon, Esq., former Senior Attorney for the Internal Revenue Service (IRS) Office of Chief Counsel and former Special Assistant United States Attorney for Massachusetts and New Hampshire
  • David N. Brodsky, Esq., 41-year veteran of the IRS Chief Counsel’s Office responsible for litigating tax cases and advising audit teams in large corporate audits
  • Jeremiah O’Sullivan, Esq., 37-year career at the IRS working as a senior appeals officer and 12 years as a professor and tax instructor
  • Paul Reska, Enrolled Agent, 20-year veteran of the IRS working as a revenue agent, offers in comprise specialist and settlement officer

Working to Resolve Your Tax Problem

Solving Tax Issues for BusinessesCompanies and business owners often come to us confused and uncertain about how to proceed when they involved in an IRS investigation or proceeding. Our tax attorneys understand the risk you and your business are up against. We will evaluate your situation, help you understand your options and work with you to resolve your tax issues.

Some of the most common tax problems businesses face include:

  • Employment and payroll tax
  • Trust fund recovery penalty
  • Excise tax
  • Income tax audits
  • Sales and use tax
  • Self employment tax audits
  • Choice of entity
  • Foreign Account Tax Compliance Act (FATCA)
  • Profit sharing
  • Planning for complex transaction
  • Small business employee health insurance credit

Helping Businesses Navigate the Tax System

At McMahon & Associates all we do is federal and state tax controversies. When you hire us, you know you are getting an experienced tax attorney, not someone who occasionally does tax cases. Tax cases are complicated and the IRS is increasing its scrutiny of businesses (see the chart below). Because 100% of our practice is devoted to tax cases, we are able to help business owners and companies navigate the tax laws efficiently and effectively.

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The information contained in the McMahon & Associates, PC web site is solely for informational purposes and does not create an attorney-client relationship or constitute legal advice. Unsolicited information transmitted electronically to our attorneys via this web site or the Internet is not considered confidential.

  • IRS to End Offshore Voluntary Disclosure Program March 13, 2018
    The Internal Revenue Service (IRS) announced on March 13, 2018 that it will be ending the Offshore Voluntary Disclosure Program (OVDP) on September 28, 2018. If you have an undisclosed foreign bank account, contact McMahon & Associates to learn how to come into compliance with the IRS. Learn more about OVDP here: IRS Offshore Voluntary […]
  • Sean McMahon Discusses Tax Trends and Challenges in Interview with Massachusetts Lawyers Weekly March 12, 2018
    In a recent interview with Massachusetts Lawyers Weekly In House Counsel, D. Sean McMahon discusses trends in tax law, challenges to the legal profession and how McMahon & Associates assists taxpayers. After leaving the Internal Revenue Service Chief Counsel’s Office in 2005, D. Sean McMahon opened the doors of McMahon Tax Law in Boston. Today, […]