Company lists · Data refreshed September 2026

Top 18 Infrastructure design companies based in Markham, Canada

RevenueBase identified 25 infrastructure design companies headquartered in Markham, Canada as of September 2026 and tracks 2,988 professional contacts across them, including 1,662 with verified work emails. Toronto is the largest hub.

This list covers infrastructure design companies headquartered in Markham, Canada, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 20, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 20, 2026 86% judged on-target in blind review
25Companies
2,988Contacts tracked
1,662Verified emails
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The 18 largest infrastructure design companies based in Markham, Canada

Ranked by team size
Top 18 of 25 infrastructure design companies based in Markham, Canada, ranked by team size, largest first. Data refreshed Sep 20, 2026. RevenueBase Smart Search rates how each company's information relates to infrastructure design companies: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 20261,001-5,0001,246 contacts →

Indirect evidence

“Our work makes the world work.”

Source: RevenueBase Database · checked Sep 20, 2026
2Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 2026501-1,000572 contacts →

Indirect evidence

“Morrison Hershfield has joined Stantec!”

Source: RevenueBase Database · checked Sep 20, 2026
3Strong evidenceMarkham, ON, CanadaHQ checked Sep 20, 2026201-500370 contacts →

Strong evidence

“LEA Group (LEA) is a privately-held, global consulting firm providing planning, engineering design, and construction administration services for urban infrastructure projects.”

Source: RevenueBase Database · checked Sep 20, 2026
4Partial evidenceMarkham, ON, CanadaHQ checked Sep 20, 2026201-500177 contacts →

Partial evidence

“PTAG is a global capital project management services company providing expertise to the Power & Utilities, Mining & Metals, Oil & Gas and Infrastructure Sectors.”

Source: RevenueBase Database · checked Sep 20, 2026
5Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202651-200131 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 20, 2026
6Partial evidenceMarkham, ON, CanadaHQ checked Sep 20, 2026501-1,000129 contacts →

Partial evidence

“Delcan is a multidisciplinary, engineering, planning, management and technology firm that provides a broad range of integrated systems and infrastructure solutions within the Rail…”

Source: RevenueBase Database · checked Sep 20, 2026
7Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202651-20084 contacts →

Indirect evidence

“Urbantech is the GTHA’s premier boutique Civil Engineering consulting firm.”

Source: RevenueBase Database · checked Sep 20, 2026
8Partial evidenceMarkham, ON, CanadaHQ checked Sep 20, 202651-20038 contacts →

Partial evidence

“At Chisholm, Fleming and Associates (CFA), we’ve been helping build Ontario’s infrastructure since 1956.”

Source: RevenueBase Database · checked Sep 20, 2026
9Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-5028 contacts →

Indirect evidence

“J+B Engineering Inc.(J+B) is a privately owned national engineering firm providing integrated multi-disciplinary consulting engineering and project management services to…”

Source: RevenueBase Database · checked Sep 20, 2026
10Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-5021 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 20, 2026
11Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-5020 contacts →

Indirect evidence

“EIS is a privately owned company focused on providing innovative engineering and project management services for the water and wastewater municipal sector.”

Source: RevenueBase Database · checked Sep 20, 2026
12Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-5012 contacts →

Indirect evidence

“Chimax Inc is a renewables & environment company based out of 3950 14TH AVE, MARKHAM, Ontario, Canada.”

Source: RevenueBase Database · checked Sep 20, 2026
13Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-5010 contacts →

Indirect evidence

“With years of development, Lake Harbour now offers a wide range of multi-disciplinary engineering services for its clients worldwide, together with the flexibility of…”

Source: RevenueBase Database · checked Sep 20, 2026
14Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 20261-1010 contacts →

Indirect evidence

“King EPCM is a full service civil engineering company that does everything outside and below a proposed building.”

Source: RevenueBase Database · checked Sep 20, 2026
15Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-509 contacts →

Indirect evidence

“HUSSON Limited is a civil engineering company based in Richmond Hill, Ontario dedicated to providing innovative, recognized and cost effective services to the Industrial…”

Source: RevenueBase Database · checked Sep 20, 2026
16Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 202611-504 contacts →

Indirect evidence

“Established in 1974, Harrington McAvan Ltd offers services in landscape architecture and environmental planning.”

Source: RevenueBase Database · checked Sep 20, 2026
17Indirect evidenceMarkham, ON, CanadaHQ checked Sep 20, 20261-101 contacts →

Indirect evidence

“PROF & E Ltd.”

Source: RevenueBase Database · checked Sep 20, 2026
18Partial evidenceMarkham, ON, CanadaHQ checked Sep 20, 2026n/a1 contacts →

Partial evidence

“Based in Markham, Ontario, Canada Connectivitywerx provides complete turnkey design/build network connectivity solutions for customers that range from deploying private fiber…”

Source: RevenueBase Database · checked Sep 20, 2026

Showing 18 of 25 infrastructure design companies based in Markham, Canada

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Infrastructure design companies based in Markham, Canada at a glance

As of Sep 20, 2026
55.6%Verified-email coverage
119.5Average contacts per company
11-50Median size (employees)
316.0%Largest-city concentration · Toronto
Sep 20, 2026Page data refreshed

Companies by employee count

1-10
3
11-50
12
51-200
3
201-500
3
501-1,000
2
1,001-5,000
1

Email recency for this list is measured across the whole Canada list rather than for Markham, so it is reported there. Company counts and contact totals on this page are exact for Markham, over 25 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among infrastructure design companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies
Companies headquartered in Markham, Canada whose own description of what they do matches “infrastructure design companies”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search
RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names infrastructure design companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude
Companies whose own description does not clearly place them among infrastructure design companies, and records with no verified work email. Companies headquartered outside Markham are excluded even when they keep an office there.
Match quality
In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every listed company carries at least one verified work email, 1,662 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 20, 2026. Lists refresh periodically as the graph is re-checked.
Corrections
Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names infrastructure design companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many infrastructure design companies are there based in Markham, Canada?

RevenueBase identified 25 infrastructure design companies headquartered in Markham, Canada as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Green Infrastructure Partners, headquartered in Markham, tops this list with the largest team on record.

Which city has the most infrastructure design companies?

Toronto leads with 79 headquartered companies, followed by Calgary (69) and Montreal (62).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 1,662 verified decision-maker contacts tracked across these 25 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 20, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.