SOC 2 vs ISO 27001: what’s the difference and which do you need?

If you’ve ever found yourself Googling SOC 2 versus ISO 27001, you’re not alone.

For growing, cloud-based businesses, understanding which framework to prioritise can quickly become confusing, especially when both start appearing in client requirements, RFPs, and sales conversations.

To cut through the noise, we sat down with Lucas Jansen, Information Security GRC Lead at LeftBrain, to unpack the differences, where each framework fits, and how to think about them as your business scales.

Can you introduce yourself and what you do at LeftBrain?

I’m the Information Security GRC Lead at LeftBrain, which means I look after governance, risk and compliance for both our internal operations and our clients.

That typically involves building out policies and procedures, managing documentation, and mapping businesses against different security frameworks and standards. A big part of the role is helping companies not just achieve compliance, but actually understand how their security operates day to day.

What are the key differences between SOC 2 and ISO 27001?

The main differences come down to geography, purpose, and how each framework is assessed.

SOC 2 is most commonly used in the United States, particularly among SaaS companies, managed service providers, and cloud-based businesses. It acts as a way of demonstrating that your service meets a defined set of security standards, assessed across five trust criteria, with security always being mandatory. In many cases, it’s driven by customer demand rather than internal need.

ISO 27001, on the other hand, is an internationally recognised standard and tends to be understood across global markets. It takes a broader view of information security, focusing on how your organisation manages risk, governance, and ongoing security practices.

There is also a structural difference in how they’re delivered. SOC 2 is typically an annual attestation, giving a point-in-time view of your controls. ISO 27001 is a certification that lasts for three years, supported by regular audits to ensure you are maintaining the standard.

When is SOC 2 the right choice, and when is ISO 27001 a better fit?

SOC 2 is particularly useful when you need to demonstrate to customers that your product or service meets recognised security expectations. This is especially true if you’re selling into US markets or operating in SaaS, where it is often seen as a baseline requirement in procurement processes.

ISO 27001 tends to be a better fit for businesses that are growing and starting to feel the strain of scaling without a clear structure. As teams expand and systems become more complex, questions around ownership, policies, and risk management start to surface. ISO provides a framework to bring those elements together in a structured way.

It’s less about ticking a box for customers and more about building internal confidence in how your business handles security, which then naturally translates into external trust.

Why is ISO 27001 often considered the cyber security backbone?

ISO 27001 is often described as a backbone because it forces you to address the fundamentals of how your business operates securely.

It requires you to define responsibilities, establish clear policies, and put processes in place that cover a wide range of security considerations. While SOC 2 can go deeper in certain areas, particularly around services and controls, ISO 27001 covers more of the overall information security landscape.

That broader coverage is what makes it such a strong foundation. Once ISO 27001 is in place, it becomes much easier to align with other frameworks, including SOC 2. In many cases, the work you’ve already done can be directly mapped across.

How does LeftBrain deliver ISO 27001 for modern, fast-moving businesses?

At LeftBrain, the focus is on making ISO 27001 work in a way that fits how modern businesses actually operate. Rather than approaching it as a heavy, one-off project, delivery is broken down into sprints, with regular working sessions that keep things moving and aligned with the business.

This allows teams to build their information security management system iteratively, without disrupting day-to-day operations. It also creates space to address challenges as they arise, rather than forcing everything into a rigid timeline.

All documentation, policies, and processes are structured within Notion, creating a centralised and connected system. This not only makes it easier to manage ISO 27001, but also enables businesses to map their work across multiple standards, including SOC 2 and Cyber Essentials.

Any final thoughts?

SOC 2 and ISO 27001 are often positioned as a choice between one or the other, but in reality, they serve different purposes.

SOC 2 is typically driven by customer requirements, particularly in US markets, and provides assurance around specific services. ISO 27001 is about building a structured, scalable approach to information security across your entire organisation.

For many businesses, the most effective approach is to start with ISO 27001 as a foundation, then layer in SOC 2 when it becomes commercially necessary. By doing so, you avoid duplication, reduce effort, and create a system that supports both compliance and growth.