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Expert Tax Lawyers

McMahon & Tivnan, PC represents individuals, estates and businesses with federal and state tax controversies, including audits, appeals, litigation and foreign transaction reporting. Collectively, our Boston tax attorneys have more than 100 years of experience investigating and defending IRS and state tax matters.

Civil Tax Controversy

McMahon & Tivnan regularly helps clients with Tax Audit Defense, Collections, Appeals, and Litigation.

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International Tax

McMahon & Tivnan advises clients on international tax matters ensuring full compliance while minimizing IRS penalties.

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Voluntary Disclosure

McMahon & Tivnan counsels clients through the IRS’s Voluntary Disclosure Program to civilly resolve tax non-compliance issues.

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McMahon & Tivnan Recent Successes

Slide 1

$21 million reduction (>80%) of IRS estate tax deficiency
(U.S. Tax Court Decision)

Slide 2

Trial victory reversing $1.4 million Massachusetts DOR tax and finding client was a Florida resident (Massachusetts Appellate Tax Board)

Slide 3

U.S. Federal District Court orders IRS to pay legal fees after denying tax lien foreclosure
(NH Federal District)

Slide 4

IRS Appeals agrees to full abatement of Form 3520 penalties
(IRS Appeals Determination)

Slide 5

$628,832 IRS income tax deficiency reversed to $520 refund
(U.S. Tax Court Decision)

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Testimonials

McMahon & Tivnan helped me through a difficult income tax examination. Sean convinced IRS that no serious penalties should be assessed despite the numerous errors committed by the companies’ prior accountants.

Boston-area business owner

Sean convinced IRS Appeals to abate a penalty of over $500,000 for failure to declare an interest in a foreign trust. Prior to retaining McMahon & Tivnan, two large, national firms could not accomplish what they did.

Retired U.S. executive living in Europe