Mairéad Hennessy

Mairéad Hennessy is the Founder and Managing Director of Taxkey, a specialist tax consultancy established in 2016. With over 20 years of tax advisory experience across all Irish tax heads, Mairéad brings a depth and range of technical expertise that is rarely found outside the largest firms.

Taxkey works as a dedicated tax partner to accountants, solicitors, and financial planners across Ireland and the UK — handling complex, high-value tax matters on their behalf, so they can deliver expert advice to their clients with confidence. For practices that want senior specialist tax support without the overhead, Taxkey fills that gap.

Mairéad specialises in succession planning for SMEs and their owners, corporate structuring and company sales, inheritance tax and estate planning, property tax (including VAT on property transactions), and cross-border and international tax for individuals and businesses moving into or out of Ireland. She also advises on Revenue investigations and disclosures.

Mairéad is a Chartered Tax Advisor (CTA AITI) and Fellow of Chartered Accountants Ireland (FCA). She holds a Bachelor of Business and Law (BBL) from UCD and a Master’s in Accounting (MAcc) from the Michael Smurfit School of Business.

She represents CCAB-I on TALC (Indirect Taxes & Direct and Capital Taxes). TALC is the main forum for engagement between Irish Revenue and the accountancy profession. She is also a former President of County Kildare Chamber (2022-2025)

Mairéad speaks regularly at professional training events and conferences, and contributes technical articles to various professional publications.

Specialist areas:

• Personal tax consultancy
• Corporate tax planning, including advice on optimum corporate structures
• VAT advisory, including VAT on property transactions
• International tax solutions for individuals moving into or out of Ireland
• Business and personal asset succession planning
• Inheritance tax advice
• Revenue investigations and disclosures