Nine Cross Border Tax Consulting Professional Corporation
- Expertise
- Team
3 of these firms are based in Thornhill; the others serve Thornhill from towns including Toronto, Mississauga and North York.
3 open 24/7 · 6 open weekends · 23 rated 4.5+
Data verified October 16, 2026
The 24 consulting firms listed for Thornhill, ON advise businesses on strategy, operations, growth and market entry. Anything stated here about their service lines and the industries they serve is taken from their own websites, and ratings come from public reviews.

23 of the 24 firms on this page have a rating, from 4.7 to 5.0 across 725 reviews; 3 have 50 or more reviews. When clients rate these firms on specific qualities, they most often praise professionalism (98%), responsiveness (69%) and quality (63%). The topics that come up most in reviews of the firms on this page are "expertise", "knowledge" and "communication". 3 are open around the clock; 6 are open on Saturdays and 3 on Sundays. Domain records put 6 websites of the firms on this page at ten or more years old; the oldest dates from 2009. 3 offer urgent consultations; 1 offers remote or virtual consultations; 2 offer payment plans; 7 offer a free initial consultation; 1 is family- or locally-owned and 2 list coupons or special offers. We have a website on file for all 24 of the firms on this page; all 24 publish a contact page; 20 list a public email and 5 take bookings online. We count these figures across the firms on this page; hours and prices change, so confirm the details with the firm before you book a consultation.
Thornhill itself accounts for 3 of the 24 firms on this page, with the others coming from other towns. Strategy work travels well over video, but operations and process reviews still want a consultant on your floor watching the actual workflow.