When to Hire a Pentest Firm vs Build an Internal Security Team

At some point, every growing company faces the same question: do we hire security people or hire a security firm? The answer is not as simple as a cost comparison, though the cost comparison is revealing. It depends on where you are in your growth trajectory, what kind of security work you need done, and what your risk profile actually looks like.

Most companies get this decision wrong in one of two ways. They either try to build an internal team too early, burning through headcount budget on a problem that does not yet require full-time staff. Or they rely entirely on external firms for too long, never building the internal capability to sustain a security program between annual assessments.

Here is a framework for making the right decision at the right time.

The Cost Comparison: What You Are Actually Spending

Let us start with the numbers, because the numbers are often the deciding factor in practice. The fully loaded cost of an internal security team versus the cost of engaging an external firm is not even close at the early stages.

The gap is stark. A single senior security engineer costs more in Year 1 than a comprehensive external testing program. And one engineer cannot cover web application testing, network testing, cloud security, code review, and compliance. You would need at least two to three people to cover the same breadth that a firm provides through its team of specialists.

But cost is only one dimension. The question is not just what is cheaper. It is what produces better security outcomes for your organization at this point in time.

When Outsourcing Makes Sense

External penetration testing firms are the right choice in several well-defined scenarios. If any of these describe your organization, you should be engaging an external partner rather than trying to build an internal team.

Early-stage companies (pre-Series B)

If you are a startup with fewer than 100 employees, you do not need a full-time security team. You need periodic, expert-level testing at defined intervals: before major launches, before compliance audits, and when your application has materially changed. An external firm gives you access to senior offensive security talent on demand, without the overhead of full-time employment. Read more about the startup security checklist before Series A.

Compliance-driven testing

If you need penetration testing primarily for SOC 2, PCI-DSS, or ISO 27001 compliance, external firms are almost always the better choice. Auditors value independence. An internal team testing their own systems does not carry the same weight as a report from an independent third party. Some frameworks explicitly require external testing.

Specialized testing needs

No single internal hire can be an expert in web application security, mobile security, cloud configuration review, Active Directory testing, social engineering, and IoT security. External firms maintain teams with diverse specializations. When you need mobile app testing this quarter and Active Directory testing next quarter, a firm can provide the right specialist for each engagement.

The fresh perspective problem

Internal teams develop blind spots. They know the system too well. They unconsciously avoid testing the authentication flow they helped build. They assume certain components are secure because they reviewed the code six months ago. External testers bring no assumptions. They attack your system the way a real adversary would, without institutional knowledge coloring their approach.

When Building an Internal Team Makes Sense

There is a point in organizational growth where an internal security team stops being a luxury and becomes a necessity. That point comes when security work is no longer periodic but continuous, and when the security decisions being made daily are too frequent and too consequential to outsource.

Continuous testing requirements

If your engineering team ships code multiple times per day and you need security review on every release, an external firm cannot keep up. You need embedded security engineers who can review pull requests in real time, participate in design reviews, and maintain security automation in your CI/CD pipeline. This typically becomes critical around Series B or when your engineering team exceeds 50-100 people.

Large and rapidly changing attack surface

If you are managing hundreds of microservices, multiple cloud environments, and dozens of integrations, the attack surface changes too fast for periodic external assessments to keep up. You need an internal team to continuously monitor, assess, and respond to changes as they happen.

Security as a product differentiator

If security is part of your value proposition to customers (you are selling to enterprises, handling sensitive data, or operating in regulated industries), you need internal security expertise that can influence product decisions, contribute to architecture, and respond to customer security questionnaires with authority.

When you need to build security culture

An external firm can test your application, but it cannot change how your engineers think about security. Building a security culture requires an internal champion who works alongside engineering teams daily, provides training, mentors junior developers, and gradually shifts the organization toward a security-first mindset. Our guide on why your first security hire should not be a CISO covers what to look for.

The Hybrid Model: What Most Mature Organizations Actually Do

Here is the reality that neither the "build" camp nor the "buy" camp wants to acknowledge: almost every organization with a mature security posture uses both. The internal team handles day-to-day security operations. The external firm provides periodic deep assessments, independence, and specialized expertise.

What the internal team owns

• Security architecture and design review for new features
• CI/CD pipeline security integration (SAST, DAST, SCA)
• Threat modeling during the design phase
• Security-focused code review for high-risk changes
• Incident detection, response, and post-mortems
• Security policy and compliance program management
• Vendor security assessments
• Security training and culture building

What the external firm owns

• Annual or semi-annual penetration testing engagements
• Compliance-driven assessments (SOC 2, PCI-DSS, ISO 27001)
• Specialized testing (mobile, IoT, hardware, social engineering)
• Red team exercises that test the internal team's detection capabilities
• Independent validation of the internal team's work

The hybrid model gives you the best of both worlds: the continuity and cultural integration of an internal team, plus the independence, specialization, and fresh perspective of an external partner.

A Decision Framework by Company Stage

The right approach changes as your organization grows. Here is a practical framework based on what we see working across our client base.

Notice that at no stage does the external firm disappear entirely. Even large enterprises with 20-person security teams still engage external firms. The value of an independent, adversarial perspective does not diminish as your internal capability grows. If anything, it becomes more important because it is the only way to test whether your internal program is actually working.

The Hidden Costs of Getting This Wrong

Building too early burns cash. A senior security engineer hired at the pre-seed stage is $200K+ per year that could be spent on product development. And a single engineer cannot provide the breadth of testing that a firm with a diverse team can deliver. You end up paying more for less coverage.

But building too late creates a different problem. Organizations that rely exclusively on annual pentests for too long end up with a year of unreviewed code between each assessment. When the pentest finally happens, the findings are overwhelming because there has been no ongoing security hygiene. The security budget conversation becomes reactive rather than strategic.

The worst outcome is the middle ground: hiring one security person too early and expecting them to replace the need for external testing. One person cannot be a penetration tester, a security architect, a compliance manager, and an incident responder simultaneously. They burn out, the program stalls, and the organization is left with neither an effective internal capability nor the external testing they stopped paying for.

What to Look for in an External Pentest Partner

If you have decided that engaging an external firm is the right move (and for most readers of this article, it is), the next question is how to choose the right one. Not all pentest firms are created equal, and the wrong choice can give you a false sense of security.

• Methodology transparency. The firm should explain exactly how they will test, what tools they use, and what their coverage looks like. If they cannot articulate their methodology, they are probably just running automated scanners.
• Relevant experience. Do they have experience testing your technology stack, your industry, and your compliance requirements? Ask for anonymized case studies or references.
• Report quality. Ask for a sample report. A good report includes proof-of-concept exploits, business impact analysis, and actionable remediation guidance, not just a list of CVSS scores.
• Communication during testing. The best firms provide real-time findings through a client portal, not just a PDF three weeks after the test ends. Critical findings should be communicated immediately, not held for the report.
• Retesting included. After you remediate findings, the firm should verify the fixes. If retesting is an add-on cost, you are incentivizing them to find as many issues as possible rather than helping you actually fix them.
• Pricing transparency. If a firm will not give you a straight answer on pricing until after three sales calls, that is a red flag. Pentest pricing should be based on scope and complexity, not on how much they think you will pay.

For a deeper dive, read our guide on how to choose a cybersecurity vendor without getting burned.

Why Lorikeet Security Is the Right Partner for Growing Companies

Lorikeet Security was built specifically for the companies navigating this decision. We work with organizations from pre-seed through Series C and beyond, providing the external testing expertise that complements whatever stage of internal security maturity you are at.

For early-stage companies that are not ready for a full internal team, we provide comprehensive penetration testing, attack surface management, and compliance-ready reports that satisfy auditors and enterprise buyers. For companies with existing security teams, we provide the independent perspective and specialized testing that validates and extends your internal program's effectiveness.

Our web application penetration testing is manual, methodology-driven, and delivered through a real-time client portal so you can track findings as they happen. We do not hold critical issues for the final report. We do not surprise you three weeks later with a PDF full of bad news. We work alongside your team as a partner, not a vendor.

Lorikeet Security Team

Penetration Testing & Cybersecurity Consulting

We've completed 170+ security engagements across web apps, APIs, cloud infrastructure, and AI-generated codebases. Everything we publish here comes from patterns we see in real client work.