Top Series A companies in Toronto

Companies that have closed a Series A — product-market fit confirmed and scaling. Filtered to companies headquartered in Toronto.

Built from a search like: “Top Series A companies in Toronto”

Ranked by current headcount across Series A companies headquartered in Toronto. Refreshed daily.

1
LifeLabs Medical Laboratory Services· Etobicoke, Ontario, Canada
- Series A
- 4.3k employees
- Founded 2011
2
JAM· Toronto, Ontario, Canada
- Series A
- 693 employees
- Founded 1996
3
Vosyn· Etobicoke, Ontario, Canada
- Series A
- 576 employees
- Founded 2023
4
Umbra· Scarborough, Ontario, Canada
- Series A
- 336 employees
- Founded 1979
5
Orium· Toronto, Ontario, Canada
- Series A
- 264 employees
- Founded 2009
6
BioRender· Toronto, Ontario, Canada
- Series A
- 227 employees
- Founded 2017
7
FacilityOS· North York, Ontario, Canada
- Series A
- 208 employees
- Founded 2014
8
Rail· Toronto, Ontario, Canada
- Series A
- 184 employees
- Founded 2021
9
Private AI· Toronto, Ontario, Canada
- Series A
- 171 employees
- Founded 2019
10
ResQ· Toronto, Ontario, Canada
- Series A
- 168 employees
- Founded 2018
11
Adeptmind· Toronto, Ontario, Canada
- Series A
- 158 employees
- Founded 2016
12
Irwin, a FactSet company· Toronto, Ontario, Canada
- Series A
- 154 employees
- Founded 2017
13
Marble· Toronto, Ontario, Canada
- Series A
- 150 employees
- Founded 2016
14
epiCura· Rivalta di Torino, Piedmont, Italy
- Series A
- 128 employees
- Founded 2017
15
Ratehub.ca· Toronto, Ontario, Canada
- Series A
- 112 employees
- Founded 2010
16
Method CRM· Toronto, Ontario, Canada
- Series A
- 112 employees
- Founded 2010
17
Horizon· Toronto, Ontario, Canada
- Series A
- 98 employees
- Founded 2017
18
Mosaic AI· Toronto, Ontario, Canada
- Series A
- 97 employees
- Founded 2021
19
Briza· Toronto, Ontario, Canada
- Series A
- 96 employees
- Founded 2016
20
Phoenix· Toronto, Ontario, Canada
- Series A
- 94 employees
- Founded 2019
21
CrowdRiff· Toronto, Ontario, Canada
- Series A
- 93 employees
- Founded 2011
22
CapIntel· Toronto, Ontario, Canada
- Series A
- 86 employees
- Founded 2019
23
OneClass· Toronto, Ontario, Canada
- Series A
- 85 employees
- Founded 2010
24
Peak Power Inc· Toronto, Ontario, Canada
- Series A
- 84 employees
- Founded 2015
25
Thornhill Medical· North York, Ontario, Canada
- Series A
- 84 employees
- Founded 2004

Find engineers at Series A companies in Toronto

Series A companies in Toronto are some of the fastest-moving employers in the market. The list above ranks the largest Series A-stage companies headquartered in Toronto by current headcount, drawn from public LinkedIn and Crunchbase records. With 129 matching companies in our index, the density of senior engineers, designers, and founders is unusually high.

At Series A, teams tend to be small, ambitious, and on the hunt for senior talent. The companies on this list are good signals for where the Torontotalent market is heating up — and for which engineers and founders are about to become tomorrow’s operators.

Refolk converts this list into a live search. Ask for “founders of Series A companies in Toronto” or “senior engineers at Series A companies in Toronto hiring” and Refolk returns a ranked shortlist with evidence behind each match.

How this list is built

Refolk pulled Series A companies headquartered in Toronto from public LinkedIn and Crunchbase records, ranked them by current employee count, and kept those with at least 5 employees. The list refreshes once a day.

Last refreshed: Thu, 07 May 2026 07:57:16 GMT

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