Ada K. Colomb
Partner
Ada K. Colomb is a Partner in Rimôn’s Trusts and Estates Group. Ada advises individuals and families on cross-border estate planning, multi-jurisdictional probate and trust administration, and U.S. tax compliance for both U.S. persons abroad and foreign nationals with U.S. ties. Her clients include U.S. citizens considering expatriation, foreign nationals relocating to or investing in the United States, and international families navigating estates and inheritances involving the United States and at least one other country.
Ms. Colomb’s practice spans the full lifecycle of international estate planning and administration. She drafts estate plans ranging from foundational documents to sophisticated trust structures, and trusts designed to qualify as domestic trusts under the IRS rules despite foreign elements. She guides families through domestic and multi-jurisdictional probate and trust administrations, advises non-U.S. beneficiaries on inheriting U.S. accounts and other assets, and counsels trustees on U.S. tax compliance and reporting obligations.
On the tax and compliance side, Ms. Colomb prepares federal and state estate (Form 706 and 706-NA) and gift tax returns, advises on expatriation and related tax consequences, including gifts and bequests from covered expatriates to U.S. citizens or trusts, and handles inbound planning for foreign nationals establishing U.S. residency or investments. She regularly handles IRS filings for foreign gifts, inheritances, and transfer certificates, often relying on tax treaties.
Ms. Colomb speaks and publishes regularly before professional audiences of attorneys, accountants, and wealth advisors. She is fluent in four languages and trained in both common law and civil code systems, enabling her to communicate directly with clients and counterparts without relying on intermediaries.
SELECTED EXPERIENCE
- Prepared tax affidavits filed with tax authorities in France, Norway, and Switzerland on behalf of U.S. estates, achieving reductions in inheritance tax of 25% to 100%
- Prepared Competent Authority request under the U.S.–U.K. tax treaty on behalf of an estate to resolve taxation by both countries of the same property
- Settled complex multi-jurisdictional probates and trust administrations involving assets and beneficiaries across Europe, Canada, Asia, the Middle East, and offshore jurisdictions
- Advised U.S. citizens on comprehensive pre-expatriation planning, including tax mitigation strategies in advance of relinquishing citizenship
- Counseled foreign nationals on inbound planning for U.S. residency, relocation, and investment, including pre-immigration trust and tax structuring
- Prepared Excluded Property Trust (U.S. domestic trust structured to meet U.K. law) designed to protect non-U.K. assets from U.K. tax
- Counseled corporate U.S. trustee of a foreign trust on U.S. tax compliance, reporting obligations, and foreign trust filing requirements
- Advised non-U.S. beneficiaries on the inheritance of U.S. retirement accounts, including IRS withholding tax considerations
- Prepared IRS Transfer Certificate applications to release U.S. assets held by non-resident decedents from U.S. estate tax lien
- Advised on obtaining U.S. tax identification numbers (ITIN, IRSN, EIN) for foreign nationals involved in U.S. estate administrations
SPEAKING ENGAGEMENTS
- Panel Speaker, “International Estate Planning,” MCLE, November 4, 2025
- Speaker, “Estate Planner’s Guide to Expatriation Planning and Taxation of Covered Gifts and Bequests under Section 2801,” Boston Probate and Estate Planning Forum, March 12, 2025
- Speaker, “Navigating Foreign Trust and International Probate: A Practical Guide,” Boston Bar Association, November 5, 2024
- Co-Presenter, “International Tax Topics,” New England Institute on Taxation, Massachusetts Association of Accountants, January 16, 2024
- Speaker, “Around the World in 60 Minutes: Tax Issue Spotting for Clients with an International Footprint,” Boston Estate Planning Council, October 26, 2023
- Speaker, “Tax and Other Issue Spotting For Clients With International Ties,” Massachusetts Wealth Counsel Annual Meeting, September 28, 2023
PUBLICATIONS
- Co-Author, “Coordinating French Tax and Civil Law with U.S. Estate Planning. A Tale of Two Systems,” Trusts & Estates, November 2025, pages 37–42
- Author, “Leaving the Stars and Stripes Behind: A Guide to Expatriation and U.S. Tax Obligations,” The International Family Offices Journal, Vol. 10, pages 39–46, September 2025
- Author, “Expatriation, Taxes and Estate Planning. Decoding Covered Gifts and Bequests Under the Final Regulations,” Trusts & Estates, June 2025, pages 19–24
- Author, “Mastering the Transfer Certificate. Key Considerations for Investors,” Trusts & Estates, November 2024, pages 36–44
- Author, “German Probate and Inheritance Tax. Strategies for Avoiding Double Taxation,” Trusts & Estates, November 2022, pages 40–48
MEMBERSHIPS & ACTIVITIES
- Society of Trust and Estate Practitioners (STEP) New England
- Vice Chair, October 2023–Present; Member since 2022
- Boston Estate Planning Council (BEPC)
- Committee Member, 2022–Present


