Thang Tax Law
1 lawyer · City of Toronto
One of 2,345 law firms listed in Toronto, and one of 133 handling Tax Law.
About Thang Tax Law
Thang Tax Law Professional Corporation is a small Toronto tax law firm led by principal Simon Thang, who holds an LL.B from Osgoode Hall Law School and an LL.M in Taxation from the London School of Economics and Political Science. Thang has over 15 years of experience focused exclusively on sales taxes, including GST/HST and provincial sales taxes, and is a member of the GST Leaders Forum, a group of 25 sales tax practitioners from across Canada. The firm is also preferred counsel for the Lawyers' Professional Indemnity Company (LawPro).
The practice covers GST/HST and sales tax, tax audits and assessments, tax appeals, and customs and trade, serving individuals, businesses, and multinationals as well as accountants and other lawyers who need specialized commodity tax support. Clients include real estate professionals, e-commerce businesses, and importers and exporters navigating CBSA disputes. Thang Tax Law was included in the inaugural 2025 edition of Best Law Firms - Canada for tax law, and Simon Thang was selected for the 19th edition of The Best Lawyers in Canada for tax law expertise.
Practice areas
Milestones & recognition
- Thang Tax Law was included in the inaugural 2025 edition of Best Law Firms - Canada for tax law.
- Simon Thang was selected for the 19th edition of The Best Lawyers in Canada for tax law expertise, announced November 12, 2024.
- Thang is a member of the GST Leaders Forum, a group of 25 sales tax practitioners from across Canada.
- The firm is preferred counsel for the Lawyers' Professional Indemnity Company (LawPro).
In the community
- Thang has taught consumption tax law as adjunct faculty at Osgoode Hall Law School and tutors the GST/HST In-Depth course for Chartered Professional Accountants.
- Thang has spoken twice at the Law Society of Ontario's Real Estate Law Summit on GST/HST issues affecting real property, including a 2021 session on rebates, exemptions and self-assessments delivered by webcast to over 1,000 lawyers.
- Thang is a frequent speaker at the CPA Commodity Tax Symposium and the Tax Executives Institute's Canadian Tax Conference, and has published book chapters, papers and articles through the Canadian Tax Foundation.
- The firm publishes a tax blog covering GST/HST and sales tax developments, including topics like e-commerce registration requirements and Ontario's non-resident speculation tax.
Good to know
Wheelchair accessible
By appointmentLawyers 1
Who handles what
The neighbourhood
Thang Tax Law's office is at 18 King Street East, an 18 storey office tower in downtown Toronto's Old Toronto neighbourhood. The building sits steps from the King subway station and connects to the underground PATH network, putting the firm within easy walking distance of the cluster of accounting and law firms concentrated around Bay Street and King Street.
That location suits a practice built around a narrow specialty. Clients come from across Ontario and beyond for sales tax and customs work, and many are referred in by other accountants and lawyers rather than dropping in locally, so being close to the professionals who send that work matters more than being close to a courthouse.
Frequently asked questions
- What areas of law does Thang Tax Law handle?
- The firm focuses on GST/HST and other sales taxes, tax audits and assessments, tax appeals, and customs and trade matters.
- The CRA is auditing my business for GST/HST, can Thang Tax Law help?
- Yes. The firm assists clients during CRA audits and can file a notice of objection if an assessment follows.
- My business received a GST/HST reassessment, what happens next?
- Thang Tax Law handles objections and appeals, including representation before the Tax Court of Canada, and notes that CRA collections can begin even while an objection is pending, so it recommends acting quickly.
- I'm an importer or exporter dealing with a CBSA audit, does the firm handle that?
- Yes. The firm advises importers and exporters on customs verifications, tariff classification disputes, duty rates, and export control questions.
- Does Thang Tax Law work with accountants and other lawyers, not just direct clients?
- Yes. The firm supports other tax and legal professionals who need specialized commodity tax expertise on a file.
- Where is Thang Tax Law located and how do I reach the firm?
- The office is at 18 King Street East, Suite 1400, Toronto. The firm can be reached at 416-601-1645 or info@thangtaxlaw.com.
Where to find them
18 King Street East, Suite 1400, Toronto, ON M5C 1C4 · 416-601-1645
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