Headless CMS content migration 101

So, you’ve finally had enough. The clunky workflows, the inflexible templates, the countless workarounds to get your content to look half-decent across devices. You’re ready for a better way of managing your organisation’s digital presence – and it starts with rethinking your CMS.

For many organisations we work with – from universities, councils and NGOs to large private enterprises – the move to a headless CMS is less of a bold leap and more of an overdue course correction. It’s about recognising that the tools you’ve relied on for the last decade simply aren’t fit for the job anymore.

But while the promise of omnichannel delivery, developer freedom, and future-proof content models is exciting, migration itself can feel daunting. Where do you start? What do you keep? How do you avoid six months of chaos?

In this blog, the first in a three-part series, we’ll walk through what a CMS migration to a headless platform really involves, why it matters, and what you can expect. In the next instalment, we’ll look at how to prepare your team and your content for the shift. And finally, we’ll explore how we’ve helped organisations simplify their migrations with Contensis – and how you can do the same.

A headless CMS separates the back-end (where your content lives) from the front-end (where it's displayed). Unlike traditional CMS platforms – where content, layout, and design are tightly coupled – a headless CMS uses APIs to deliver your content to any digital channel.

A Headless CMS is made up of three main parts:

• Content models define how your content is structured – what fields it contains, what metadata it requires, and how it relates to other content types. This is what makes content modular, reusable, and scalable.
• APIs are the mechanism that delivers your content to your website, apps, and other channels. Rather than being locked into templates, your content becomes flexible and portable – ready to be used wherever it’s needed.
• Modular content shifts your mindset from building pages to creating reusable content components. For example, a news article might be made up of a title, summary, body text, image gallery, and tags – each stored and managed separately, but brought together dynamically on the front end.

Think of a traditional CMS like a restaurant with a fixed menu and a kitchen that only serves food in one way – say, plated meals for the dining room. In this scenario, everything is bundled together: the kitchen (your content management tools) and the presentation (your website) are tightly linked. If you want to serve the same food as takeaway, through a drive-thru, or at a festival, you're out of luck – the system simply wasn’t built for that.

A headless CMS, on the other hand, is like having a central kitchen that prepares high-quality ingredients and meals, ready to be served anywhere – in the restaurant, through a food truck, via delivery apps, or even at a pop-up stall in another country. You still control what’s cooked and how it’s prepared, but the presentation is completely flexible. You can serve the same content – consistently and efficiently – across your website, app, digital screens, or whatever comes next.

This separation allows developers and content creators to work independently but toward the same outcome. Your dev team can use modern tools and frameworks to build fast, responsive interfaces, while your content team manages structured, reusable content that can be delivered anywhere.

During a headless CMS migration, this new separation of concerns becomes a central design principle. It requires a rethink of how content is modelled, how teams collaborate, and how technology is integrated across your digital estate. That might mean retiring legacy templates, unpicking hardcoded content, or decoupling front-end elements that have historically been baked into your CMS.

The result? A system that's easier to maintain, more adaptable, and ready for future platforms and audience needs.

For organisations managing complex digital estates, especially those needing to serve multiple audiences or brands, it’s a game-changer.

If you’ve inherited a legacy CMS setup, chances are you already know the pain: duplicated content, clunky editing workflows, slow release cycles, and limited integration with the rest of your digital tools.

A headless CMS addresses these challenges directly by allowing you to:

• Scale effortlessly as your content and traffic grow
• Publish across multiple platforms with ease
• Give developers flexibility to work with the best tools
• Future-proof your tech stack with an API-first approach

Broken down by role, this means that:

• Spend less time copying and pasting across templates or sites
• Create once, publish everywhere – from websites to microsites, apps to screens
• Work in a clean, modern editing environment designed around reusable content

• Use their framework of choice (React, Vue, etc.)
• Build faster, more secure front ends
• Integrate easily with APIs and external systems (CRMs, analytics, marketing platforms)

• Future-proof digital infrastructure
• Respond quickly to new channels and audience demands
• Reduce long-term cost and complexity

Before their migration, one university we worked with had three separate CMS instances just to manage content for their domestic and international websites. Each change – whether to course pages or policies – needed to be manually replicated across systems. After migrating to a headless setup with Contensis, they created a centralised content model and now publish consistently across all sites, saving time and reducing errors.

Sticking with a legacy CMS may seem cheaper in the short term, but it often leads to long-term risks: security gaps, brittle integrations, and digital teams stretched thin by repetitive tasks. Migrating to a more future-proof CMS isn’t just about changing platforms – it’s about changing what your team is capable of delivering.

Before diving into technology decisions or front-end frameworks, the real work starts with content. If you don’t know what you’re migrating, how it’s structured, or who needs to manage it, you’re walking into the unknown.

This is the point where many migrations fail – not because of technical missteps, but because the groundwork wasn’t laid properly. A successful CMS migration starts by understanding your current state and making informed decisions about your future content structure, workflows, and responsibilities.

A good starting point includes:

• Auditing your content: What exists, what still serves a purpose, and what needs rewriting or archiving?
• Identifying pain points: Where does your current CMS fail your editors or frustrate your users?
• Mapping your stakeholders: Who needs to be involved, and who needs to buy in?

From here, you can move onto domain modelling and content modelling – two critical steps in ensuring you get the most from a headless setup.

Domain modelling is the foundation of a well-structured digital estate. It involves identifying and mapping the core entities your organisation deals with – such as courses, departments, staff profiles, events, services, or news stories – and understanding the relationships between them.

You’re not just naming content types here. You’re clarifying how each entity interacts with others and where they sit in the bigger picture. For example, a university course might be delivered by a department, taught by a member of staff, and linked to a location or campus. Mapping these relationships gives your content structure meaning and flexibility.Getting this right allows you to design a CMS that reflects your organisation’s logic – not just your website’s layout. It also helps avoid duplication, encourages reuse, and ensures a consistent user experience across different channels.

Start by whiteboarding the key entities. Then, draw out their relationships. What depends on what? Where are the shared attributes? Which ones are standalone, and which are nested within others? Tools like Miro or Lucidchart can be helpful at this stage to visualise your thinking.

Once you’ve mapped your domain, content modelling gets into the details: what fields make up each content type, and how are those fields structured?

Let’s take the example of a “Course” content type. It might include:

• Course title
• Summary description
• Modules
• Entry requirements
• Tuition fees
• Related subjects
• Department or faculty
• Campus location

Each of these fields needs to be clearly defined so your editors know exactly what to input, and so your developers can output the right content wherever it’s needed. You also need to decide things like:

• Which fields should be required and which should be optional?
• Can fields be reused or referenced across types?
• Are any fields restricted to certain roles or workflows?

Good content models balance flexibility and control. Too rigid, and editors feel boxed in. Too loose, and content becomes inconsistent and hard to reuse.

You’ll also want to consider how different content types relate to each other. Can a staff profile be linked to multiple departments? Should an event be tagged to a specific location or audience type? Modelling these relationships at the start saves huge amounts of rework later.

A well-structured content model not only makes your migration smoother, it also sets you up for more efficient publishing, better governance, and an easier time integrating with search, personalisation, or analytics tools.

By this point you’ve audited your content, understood your workflows, and designed solid domain and content models. You’ve set the stage – now it’s time to move into the migration itself.

A headless CMS migration isn’t something you can brute-force over a week. It involves planning, sequencing, and collaboration across departments. Each stage involves decisions that affect how your teams work, how your systems connect, and how your users experience your digital estate. The goal is to move with purpose – not just to get everything moved, but to make sure what you move actually works better than before.

There’s no one-size-fits-all approach to migration. Your priorities, your systems, and your content all play a part in shaping how this process runs. That said, here’s the process we typically follow with clients. Note that our involvement typically begins at stage two, once an organisation has selected Contensis as their new CMS:

• Evaluate your needs. What does your organisation need from a CMS?
• Shortlist CMS platforms. Compare features, pricing, and support. Focus on long-term scalability, not just short-term wins
• Test options. Trial potential platforms to see how they fit your workflows.

• Audit existing content for quality and relevance. What stays, what goes, and what needs an update?
• Define content models. Plan modular structures for scalability.
• Set clear goals. Align migration objectives with business priorities like faster time-to-market or improved user experiences.

• Set up the CMS. Configure content models, metadata, and taxonomies.
• Integrate systems. Connect essential tools like CRMs, analytics, and marketing platforms.

• Automate where possible. Use scripts or migration tools, such as the Contensis CLI.
• Tidy up manually. Review and refine complex content.
• Test content. Check everything displays correctly across any integrated platforms.

• Build new interfaces using frameworks like React, Vue, or Angular.
• Adapt your current front-end if you're keeping your existing design.
• Connect to APIs for seamless content delivery.

• Test API performance and front-end responsiveness.
• Conduct user testing to make sure everything works perfectly across devices.

• Launch your new site with a phased rollout or all at once. We recommend an iterative launch whenever possible.
• Monitor performance by tracking API and user experience metrics.
• Refine and improve by gathering feedback and making adjustments post-launch.

A successful migration isn’t just about ticking off tasks – it’s about building confidence and clarity as you move from one phase to the next. By following a structured, realistic approach, you’ll reduce risk, keep your teams aligned, and make sure your new CMS delivers on its promise.

Even the best-planned migrations can hit a few snags. Here are some of the most common challenges we've seen – and how to overcome them.

Legacy content can be messy, inconsistent, and tied to old templates or hardcoded structures. Automating the migration of high-value content can save time, but some pieces will always need a human touch. Prioritise what matters most – like frequently visited pages or user-critical information – and plan manual cleanup in sprints.

It’s common to discover that no one knows who owns certain pages or sections of your websites. Clarify content ownership early. Assign responsibility for reviewing, rewriting, and approving content to specific individuals or teams, and document it in your content strategy.

New workflows and tools can feel daunting, especially if people are used to a traditional CMS. Don’t wait until go-live to involve your editors. Offer early access to prototypes, run walkthroughs, and provide clear documentation. The more familiar your teams are, the smoother the transition.

Connecting the CMS with your other tools (like CRMs, analytics, or other business systems) can be challenging if APIs aren’t well-documented or if legacy systems need custom workarounds. Collaborate with developers from the start and build in time for trial-and-error. Test small and scale gradually.

There’s no avoiding it – migrations require a budget. But focusing purely on upfront cost can obscure long-term value. Headless setups reduce technical debt, make future changes easier, and empower teams to do more with less. Frame migration as a strategic investment, not just a tech upgrade.

Migrations expose content that’s outdated, duplicated, or poorly written. Rather than transferring everything, treat the migration as an opportunity to improve. Create guidelines for tone, structure, accessibility, and tagging and apply them consistently during the process.

CMS migration isn’t about flipping a switch. It’s about laying the right foundations – starting with a clear understanding of what your content actually is, how it needs to behave, and who needs to use it.

In the next post, we’ll look at five practical steps to make sure your migration starts on the right foot, covering everything from content audits to stakeholder wrangling and early team buy-in.