October 2025 saw two of the world’s biggest cloud service providers suffer major outages – Azure from Microsoft and Amazon’s AWS. Given the extensive footprint of these two behemoths of the cloud computing world, the impact was widespread and significant. The outages also brought into even sharper focus an issue that has been creeping up the priority lists of both tech and business leaders – building cloud resilience.

In this blog, we’re going to quantify what is known as cloud concentration risk. We’ll look at the main solutions, the additional challenges that come with those solutions, and what you should do next.

Cloud Concentration Risk

The starting point is to explore the issue – cloud concentration risk. Cloud concentration risk arises when you depend on one cloud provider. It’s a risk that is potentially severe operationally, financially, and reputationally.

Your cloud concentration risk is 100 percent if you only use one cloud service provider, such as, for example, AWS. In simple terms, if your cloud concentration risk is 100 percent and your cloud service provider suffers an outage, you essentially suffer the outage too.

But this is a risk that goes beyond using a single provider, as your cloud concentration risk is still high if you are overly reliant on a single cloud provider.

Key aspects of cloud concentration risk include:

• Single-provider dependency for applications, data, or workloads.
• Systemic concentration where companies within the same sector are overly reliant on a single cloud services provider.
• Geographical concentration within a single provider.
• Service-layer concentration where third-party components that you rely on are also heavily reliant on a single cloud services provider.

The last point above is important to explore a bit further, as mitigating cloud concentration risk in your organisation means looking beyond the parts of your infrastructure that you control.

Cloud Concentration Risk and Regulatory Compliance

Cloud concentration risk is also a key compliance issue in some industries, with regulators and governments implementing frameworks and legislation that set standards to mitigate the risks. The financial services industry is a primary example, with regulators in the UK and Europe publishing resilience frameworks. US financial services regulators are also increasingly looking at cloud concentration risk management.

Building Cloud Resilience

The solution to mitigating cloud concentration risk is to build cloud resilience, i.e., reducing your dependence on any single cloud service provider. There are three main components of a cloud resilience strategy:

• Options – you need tried and tested protocols that ensure you can continue as close to business-as-usual as possible when a cloud service provider goes down, i.e., no single provider suffering an outage should result in a halt to major parts of your operation.
• Fast response – the response to an outage from a key cloud service provider should be fast and, where possible, automated.
• Minimally disruptive – overall, there should be minimal disruption to customers, users, and your business operations.

How to Build Cloud Resilience – The Main Options

Hybrid Cloud

A hybrid cloud approach involves transitioning to an IT architecture that utilises two or more types of cloud environments. While there are multiple approaches, this typically involves an on-premises or hosted private cloud and one or more public clouds, e.g., AWS, Azure, Google Cloud, etc. This architecture creates a unified, flexible computing environment that helps to mitigate cloud concentration risk and build cloud resilience.

Multi-Cloud

A multi-cloud approach involves using two or more public cloud service providers. This can include the big three – AWS, Azure, and Google Cloud – as well as smaller providers.

Multi-Region

A multi-region strategy involves distributing your applications, data, and workloads across different geographical regions. This could be with a single provider or utilising a hybrid or multi-cloud strategy.

Additional Considerations

Additional considerations that can also improve your cloud resilience and reduce your risk exposure include:

• Edge services, where computing and networking functions are moved closer to data sources or users rather than relying entirely on a centralised cloud.
• Automated failover mechanisms.
• Backup and restore protocols.
• Continuous monitoring.
• Risk assessments to continuously evaluate cloud concentration risk exposure.
• Contractual safeguards to optimise service-level agreements, especially exit clauses.

Building Cloud Resilience – The Challenges

• Data portability – it isn’t always straightforward to transfer data between cloud service providers. After all, cloud providers want you to be locked in as it benefits their business model. As a result, many providers make it easy to migrate in, but it can be challenging to migrate out. Compatibility issues can also arise
• Integration challenges – the impact of integration complexities between cloud environments.
• Migration challenges – migration discrepancies can arise, leading to data inaccuracies.
• Geographical and jurisdiction concerns – as different locations around the world have different regulations, laws, requirements, and standards.
• Management – additional management considerations (such as ensuring security policy consistency) and skills requirements often also need to be overcome.

Developing and Implementing a Cloud Resilience Strategy

This blog gives an overview of cloud concentration risk and the main options for mitigating that risk by building cloud resilience. The precise makeup of a cloud resilience strategy will be unique to your organisation. As a result, it is important to work with a service provider that has experience implementing cloud resilience solutions in enterprise organisations.
We have that experience and expertise at Accessplc, including in highly regulated environments such as the financial services sector. Get in touch to arrange a consultation.