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Cyber Security Firms

Best Cyber Security Firms in Chicago

Chicago is a financial and logistics hub where a large share of the demand comes from mid-sized firms in banking, trading, transport and manufacturing that have to answer to regulators before they answer to customers. The firms on this list were checked the same way as every list on the site. Rank one is the best overall, ranks two to four are the best for small business, managed detection and compliance work, and the rest cleared the same checks.

10 firms ranked20 evaluatedChecked
  1. 01Best overall
  2. 02Best for small business
  3. 03Best for managed detection
  4. 04Best for compliance
  5. 05+The rest of the shortlist, ranked on the same checks
Rank 01
HALOCK Security Labs logo

HALOCK Security Labs

Best overall

A privately owned risk and compliance consultancy that wrote the risk method it assesses against.

Checked
Why they are on this list
  • Principal authors of the CIS Risk Assessment Method and board members of the Duty of Care Risk Analysis Council, so the risk method it assesses clients against is published and can be read before the engagement starts
  • Carries the PCI Qualified Security Assessor credential alongside HIPAA, CMMC and ISO 27001 compliance work, which means the firm that finds a gap can also perform the assessment that closes it
  • States more than three decades of experience testing networks, applications, wireless environments and security controls, across ten named test types: external and internal network, wireless, assumed breach, adversary simulation, red team and web application among them
  • Publishes a separate incident response hotline, 800-925-0559, rather than routing a live incident through a contact form
  • Privately owned and operated from one headquarters at 1834 Walden Office Square in Schaumburg, not as a regional office of a national practice
Attestations
PCI QSA
Sectors
Financial services, Health care, Legal, Manufacturing, Education, Energy
Risk management and CIS RAM assessmentsPenetration testing and adversary simulationCompliance validationIncident response and forensics$$Schaumburg, IL
Visit website, HALOCK Security Labs847-221-0200
Rank 02
LeadingIT logo

LeadingIT

Best for small business

A Chicagoland managed IT and security provider that scopes for companies of 25 to 200 staff.

Checked
Why they are on this list
  • States plainly that its cybersecurity work is built for businesses with 25 to 200 employees, the band most managed security firms treat as too small to scope properly
  • Publishes response commitments rather than describing them: a 15 minute response on critical issues, a one hour on-site response for urgent problems, and 24/7/365 support
  • Offers a 60 day satisfaction guarantee, which puts a stated exit on a managed contract that normally runs a year or more
  • Runs four Illinois offices, in Woodstock, Chicago, Naperville and Manteno, and states it covers northern Illinois, southern Wisconsin and northwestern Indiana
  • A three time Inc. 5000 honoree, also listed on the MSP 501 managed service provider ranking
Founded
2010
Sectors
Banks, CPAs, Law firms, Manufacturing, Municipalities, Private schools
CybersecurityCo-managed ITOutsourced IT supportIT compliance$Woodstock, IL
Visit website, LeadingIT815-788-6041
Rank 03
DefendEdge logo

DefendEdge

Best for managed detection

A managed detection provider running its own staffed operations center in the Chicago suburbs.

Checked
Why they are on this list
  • Runs a 24/7/365 security operations center in Chicago staffed by human analysts, and states the staff is entirely US-based with no offshoring
  • States more than 85 US Department of Defense veterans on staff and that it hires US citizens for the operations center, which is what a US-based claim has to mean to be checkable
  • Sells managed detection and response, endpoint detection and response and SIEM as named products with their own teams, not as a security tier bolted onto a helpdesk contract
  • Operates its own threat intelligence platform, iDNA, so the detections its analysts act on come from a source the firm controls rather than a resold feed
  • Founded in 2017 and headquartered at 505 West Grand Avenue in Elmhurst, inside the metro rather than in a distant follow-the-sun center
Founded
2017
Sectors
Financial services, Healthcare, Retail, Energy, Education, Government
Managed detection and responseEndpoint detection and responseSIEMThreat intelligence$$Elmhurst, IL
Visit website, DefendEdge872-302-1100
Rank 04
VikingCloud logo

VikingCloud

Best for compliance

A payments-focused assessor and managed security firm with Chicago as one of its two headquarters.

Checked
Why they are on this list
  • States more than 100 Qualified Security Assessors across 16 countries, which is the credential a merchant needs before anyone can sign a PCI DSS report on compliance
  • Names Chicago as a headquarters alongside Dublin, so the assessment and account teams sit in US business hours rather than answering a ticket overnight
  • States 1,000 cybersecurity and compliance staff and more than 4 million business locations protected, which is the scale card payment assessment work runs at
  • Sells the assessment and the monitoring under one roof, so a merchant that fails a scan has the same firm remediating and re-testing it
  • Sector focus is stated and narrow: retail, restaurants, hotels, pharmacies, fuel and convenience stores and auto service, all card-present businesses
Size
Over 500 staff
Attestations
PCI QSA
Sectors
Retail, Restaurants, Hotels and hospitality, Healthcare, Fuel and convenience
PCI DSS compliance assessmentManaged security servicesPenetration testingVulnerability scanning$$Chicago, IL
Visit website, VikingCloud
Rank 05

Sikich

A Chicago professional services firm running security alongside audit, tax and managed IT.

Checked
  • Named to MSSP Alert's Top 250 MSSPs list for 2025 at number 49, which is an independently scored placement rather than a directory badge
  • Around 2,000 professionals across the firm, so an incident gets a bench behind it rather than the one consultant who sold the work
  • Acquired Burwood Group, a Chicago security and network consultancy in operation since 1997, which added a security consulting practice next to the managed services side
  • Publishes what the compliance work covers: PCI DSS, HIPAA and GLBA assessments, SOC 1, 2 and 3 reporting, and CMMC support
  • Runs security inside a firm that also does audit and tax, so a regulated Chicago business can scope an assessment with people who already read its financial controls
Size
Over 500 staff
Sectors
Financial services, Manufacturing, Government, Insurance, Life sciences, Nonprofit
Managed IT servicesPenetration testingCompliance auditsIncident response$$Chicago, IL
Visit website, Sikich877-279-1900
Rank 06

Netrix Global

A north suburban IT and security provider in operation since 1989, with round-the-clock monitoring.

Checked
  • In operation from Bannockburn since 1989, a longer unbroken run in the Chicago market than almost any firm still selling security here
  • States more than 600 engineers, so a security engagement draws on the same bench that already runs the network, cloud and identity work
  • Security analysts monitoring for threats around the clock is written into its managed service as a standing phase, not offered as a paid escalation
  • Names financial services, manufacturing, legal, education and professional services as its sectors, which is close to a map of the Chicago mid-market
Founded
1989
Size
Over 500 staff
Sectors
Financial services, Manufacturing, Legal, Education, Professional services
CybersecurityManaged servicesAdvisory servicesCloud platform$$Bannockburn, IL
Visit website, Netrix Global
Also on the shortlist
Rank 07

West Monroe

A Chicago-founded consultancy whose security practice is advisory and diligence work, not monitoring.

Website, West Monroe
Rank 08

Ascend Technologies

A mid-market managed IT and security provider with a Chicago office and a staffed operations center.

Website, Ascend Technologies
Rank 09

PSM Partners

A Loop-based managed service provider with a managed security operations center as a named line.

Website, PSM Partners
Rank 10

Nexum

A veteran-owned managed security provider founded in Chicago, running combined security and network operations centers.

Website, Nexum

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How to Choose a Cyber Security Firm in Chicago

Chicago's security market is shaped by who the buyer answers to. A proprietary trading firm on Wacker answers to an examiner, a hospital group answers to the Office for Civil Rights, and a restaurant group answers to its acquiring bank. Each of those is a different first purchase, so start with the requirement and work back to the vendor.

If the requirement is an assessment, look the credential up on the certifying body's register. A PCI DSS report on compliance can only be signed by a Qualified Security Assessor, and a firm that says it helps with PCI without holding that credential is going to subcontract the signature. If the requirement is monitoring, ask where the operations center sits and whether the analysts are employees. Two firms here run round-the-clock centers inside the metro, which is the difference between an alert reviewed at three in the morning and one queued until the shift starts.

Whatever the requirement, ask which controls the firm would put in first. If the answer does not begin with email security, phishing resistance and multi-factor authentication, the proposal is selling tooling rather than closing the routes attackers actually use.

Finally, ask what happens on day one of an incident. The steps that follow a breach are the same everywhere, but a firm in the collar counties can put people on site the same afternoon, and after ransomware that is usually worth more than a lower monthly rate.

What the Ranks Mean

Rank one is the best firm overall on the checks in the editorial policy. Ranks two to four are the best firm for one kind of buyer each: a small business, an organization buying managed detection, and an organization facing compliance work. The rest of the shortlist cleared the same checks and is ordered on them. A low rank on this list is not a warning; a firm that failed a check is not on it.

Questions about hiring a cyber security firm

What do cyber security firms in Chicago charge?

The firms on this list price three different things. Managed detection and response is sold per device or per user per month, and a fifty-person company usually budgets a few thousand dollars a year for it. Penetration tests are scoped projects, commonly a few thousand dollars for an external network test and more for a web application. Compliance assessments and incident response are quoted per engagement. Ask for a starting range before the discovery call.

Do I need a cyber security firm based in Chicago?

For monitoring, no. A security operations center watching your endpoints works the same from Elmhurst or from Denver. For incident response, compliance assessments and anything touching your offices, staff or physical systems, local matters. An assessor who can be at your Loop office the next morning shortens a PCI DSS or CMMC engagement, and after ransomware the forensics team often needs hands on the machines.

What does Illinois law require after a data breach?

The Personal Information Protection Act, 815 ILCS 530, requires any business holding personal information about Illinois residents to notify them in the most expedient time possible and without unreasonable delay. If a single breach means notifying more than 500 Illinois residents, the business must also notify the Illinois Attorney General, no later than when it notifies consumers, describing the breach, the number affected and the steps taken.

How does BIPA change what a Chicago business needs from a security firm?

The Biometric Information Privacy Act, 740 ILCS 14, requires written consent before a business collects fingerprints, face scans or voiceprints, and gives the individual a private right of action worth $1,000 for a negligent violation and $5,000 for an intentional or reckless one. An amendment effective August 2, 2024 limits recovery to one violation per person per collection method. A firm advising a Chicago employer on time clocks or access control should name BIPA unprompted.

Which industries drive cyber security demand in Chicago?

Trading and banking sit at the top, because the exchanges, proprietary trading firms and community banks all answer to examiners who ask about vendor risk and incident response plans. Healthcare systems and their suppliers need HIPAA work. Retail, restaurant and hospitality groups need PCI DSS assessments, which is why two firms on this list keep Qualified Security Assessors on staff. Manufacturers and logistics operators increasingly face CMMC and customer security questionnaires.

What should I ask a Chicago cyber security firm before hiring it?

Ask who answers an alert at three in the morning, and whether they are employees or a subcontracted overnight desk. Ask for the certifying body's register entry for any credential the firm lists, rather than a logo on a slide. Ask what the firm does in the first hour of a ransomware incident and whether that is included or billed separately. Then ask for a starting range for the exact engagement you described.

How is this list put together?

Every firm is checked on what it actually does, the attestations that can be verified, its track record, a response test where we contact it as a prospective client, and how clear it is about scope and price. Rank one is the best firm overall. Ranks two to four are the best for small business, managed detection and compliance. The editorial policy sets out each check and what fails it.

Ranked lists in other cities

Each metro is researched on its own. A firm that leads nationally does not automatically appear on a city list, and most city leaders are not national names.

The national ranking