CMS Vendor Lock-In Explained: Sanity vs Payload 2026

Every headless CMS comparison mentions "vendor lock-in" like it's a binary switch — either you're locked in or you're not. After shipping production sites on both Sanity and Payload CMS and auditing their ecosystems in detail, I can tell you it's more nuanced than that. Lock-in isn't one thing. It's at least five different things, and understanding which ones actually matter for your project is the difference between making a smart trade-off and discovering an expensive mistake eighteen months from now.

This article breaks down what lock-in actually looks like in practice when you're choosing between a hosted platform like Sanity and a self-hosted framework like Payload.

Lock-in is not binary

The open-source community tends to frame lock-in as a moral question: proprietary bad, open-source good. That framing is too simple to be useful. Every technology choice creates dependencies. The real question isn't "does this create lock-in?" — it's "what specifically am I locked into, what would it cost to leave, and is that cost justified by what I get?"

Let me walk through five distinct types of lock-in that show up when you're evaluating a headless CMS, with concrete examples from Sanity and Payload.

1. Data storage lock-in

This is the one everyone talks about, and it's the most straightforward.

Sanity stores your content in the Content Lake — a proprietary, managed data store that you access through GROQ queries or their API. You don't have a database connection string. You can't point another tool at your data and read it directly. Sanity provides export tooling, so your data isn't trapped, but at runtime your content only exists inside Sanity's infrastructure.

Payload stores your content in your own database — Postgres, MongoDB, or SQLite through official adapters. You have a connection string. You can query that data with any tool that speaks SQL or MongoDB's query language. If you stop using Payload tomorrow, your content is sitting in a standard database that every framework on earth can connect to.

This distinction matters most when you think about what happens if you need to leave. With Payload, switching CMS frameworks means building a new admin panel and API layer on top of your existing database. With Sanity, switching means exporting your content from the Content Lake, transforming it into whatever format your new system expects, and rebuilding your data access layer from scratch.

The practical cost of Sanity's data lock-in depends on how much content you have and how complex your references and content structures are. For a blog with 200 posts, migration is an afternoon. For an e-commerce catalog with 10,000 products, nested variants, and cross-referenced categories, it's a significant engineering project.

2. Query language lock-in

This one gets overlooked, and in my experience it's actually more expensive than data storage lock-in.

Sanity's GROQ is a powerful, purpose-built query language. It lets you shape, filter, join, and project data in ways that are genuinely elegant. But GROQ only works with Sanity's Content Lake. Every query you write, every data-fetching pattern you build, every utility function that shapes API responses — all of it is coupled to a language that has exactly one backend.

Here's what that looks like in practice. A typical Next.js page component using Sanity might have a GROQ query like this:

*[_type == "product" && category->slug.current == $slug]{
  title,
  "image": mainImage.asset->url,
  price,
  "variants": variants[]->{title, sku, inventory}
}

That query encodes business logic (how products relate to categories, how variants are structured, what fields to expose) in a Sanity-specific syntax. If you move to a different CMS, you're not just migrating data — you're rewriting every query across your entire frontend.

Payload's approach creates a different kind of coupling. You write queries using Payload's find, findByID, and where syntax through the Local API, REST API, or GraphQL. These are Payload-specific too, but the underlying data model maps directly to your database schema. If you leave Payload, your queries need rewriting, but the mental model (collections, fields, relationships in a relational or document database) transfers directly to whatever you build next.

Neither approach is lock-in-free. But Sanity's query lock-in runs deeper because GROQ is a proprietary language tied to a proprietary backend, while Payload's query patterns sit on top of standard database concepts.

3. Pricing lock-in

Pricing lock-in is the constraint that tightens gradually. It's not about whether you can afford the CMS today — it's about what happens to your costs as you scale, and how hard it is to leave once your team and workflows are built around the platform.

Sanity charges per seat ($15/month on Growth) plus metered usage: API requests, bandwidth, documents, and assets. The per-seat model means your CMS cost grows linearly with your editorial team. The metered resources mean your cost also grows with traffic and content volume. On lower tiers, these aren't just billing items — they're hard caps that can block operations if you exceed them.

The lock-in dynamic works like this: your editorial team learns Sanity Studio, builds workflows around Comments and Tasks, creates content using Portable Text and custom components. Six months in, switching CMS would mean retraining editors, rebuilding content entry workflows, and migrating all that structured content. So when Sanity's pricing increases or your usage crosses into a more expensive tier, the switching cost is high enough that you absorb the price increase.

Payload's core is MIT-licensed and free forever. There's no per-seat pricing for the CMS itself. Your costs are infrastructure: hosting, database, storage, and the engineering time to maintain it all. The lock-in here is operational rather than financial — you've invested in a deployment pipeline, monitoring, backup strategy, and your team's familiarity with Payload's config and plugin system. Switching away means rebuilding that operational layer, not escaping a pricing tier.

The key difference: with Sanity, the platform controls pricing and can change it. With Payload, your costs are spread across commodity infrastructure providers where competition keeps prices stable and switching between providers (different Postgres hosts, different S3-compatible storage) is relatively straightforward.

4. Schema and content model lock-in

Both Sanity and Payload use code-defined schemas, which is good — your content model lives in version control, not in a GUI that can't be exported. But the specifics of how each platform models content create different kinds of lock-in.

Sanity schemas use a JSON-based format with Sanity-specific types like reference, image (with asset pipeline integration), slug, and block (Portable Text). Portable Text is particularly worth understanding here. It's Sanity's rich text format — an open specification, technically, but in practice it's a deeply nested JSON structure that requires Sanity-specific rendering libraries to turn into HTML. If you've built your entire site around Portable Text with custom block types and inline annotations, migrating that content to another CMS's rich text format is a significant transformation project.

Payload schemas are TypeScript configurations that map to database columns and documents. Rich text uses Lexical (or Slate in older versions) — these are general-purpose rich text editors with their own serialization formats. Payload's block system creates structured JSON in your database that you render with your own components. The content model maps more directly to database primitives, which makes it more portable, but you're still coupled to Payload's specific field types, hooks, and access control patterns.

The practical impact: if you're evaluating how much schema lock-in matters, look at your rich text complexity. Simple text with headings and links migrates easily from either platform. Complex rich text with custom blocks, inline components, and nested structures is expensive to migrate from either platform, but especially from Sanity's Portable Text because of its unique serialization format.

5. Ecosystem and integration lock-in

The last type is the softest but most pervasive. It's the accumulated weight of every plugin, integration, and workflow pattern that ties your project to a specific ecosystem.

Sanity has years of mature plugins, official framework starters (Next.js, Nuxt, Astro, React Router), and deep integrations with services like Vercel and Netlify. The Presentation tool for visual editing, the next-sanity package for preview and live editing, and the image pipeline with automatic transforms — these are powerful features that become load-bearing parts of your architecture. Replacing them means finding or building equivalents.

Payload's ecosystem is newer but growing fast (40,000+ GitHub stars as of early 2026). It has official plugins for SEO, form building, multi-tenancy, redirects, and search. Because Payload runs inside your Next.js app, its integrations tend to be tighter — but that also means they're more coupled to your application code. Extracting Payload from a project where you've used hooks, access control functions, and custom admin components throughout your app is a deeper surgery than removing a headless API call.

What does migration actually cost?

Let me put rough numbers on this based on projects I've worked on and migration reports I've reviewed.

Migrating away from Sanity for a mid-sized project (50-100 document types, 5,000+ documents, Portable Text with custom blocks, GROQ queries across 30+ page templates) is typically a 3-6 week engineering effort. The bulk of the time goes into content transformation (especially Portable Text to a new rich text format) and query rewriting (GROQ to whatever your new system uses).

Migrating away from Payload for a comparable project is typically 2-4 weeks, because your data is already in a standard database and your rich text is in a more portable format. The time goes into rebuilding your admin interface, reimplementing access control logic, and replacing any hooks or custom server-side logic that runs through Payload's pipeline.

These are rough estimates and your mileage will vary significantly based on content complexity, custom features, and team familiarity. But the pattern holds: Sanity's proprietary data layer and query language add meaningful migration cost compared to Payload's standard database approach.

When lock-in is worth it

I want to be clear: lock-in is not inherently bad. Every technology choice creates dependencies, and sometimes the value you get is worth the switching cost you accept.

Sanity's lock-in is worth it when the hosted infrastructure, visual editing, editorial workflow tools, and GROQ's query power save your team enough time and operational headache to justify the dependency. For marketing teams that need to ship content fast, for editorial organizations that need collaboration tools out of the box, and for projects where the CMS is infrastructure rather than the core product — Sanity's managed approach can be the right call.

Payload's operational burden is worth it when data control, regulatory compliance, pricing predictability, and architectural flexibility are non-negotiable requirements. For multi-tenant SaaS applications, for regulated industries, for projects where the CMS is deeply integrated with custom business logic — owning your infrastructure is the right call.

How to evaluate lock-in for your project

Here's the framework I use with clients. For each type of lock-in, ask two questions: "What's the probability I'll need to leave?" and "What's the cost if I do?"

If you're building a marketing site for a well-funded SaaS company that's been around for five years, the probability of needing to migrate CMS platforms is low. Sanity's lock-in is a reasonable trade-off for its editorial tooling and managed infrastructure.

If you're building a product where the content layer is core to your business model, where you might need to change CMS platforms as requirements evolve, or where regulatory requirements could shift — the probability of needing to leave is higher, and you should weight the migration cost more heavily. Payload's portability becomes a more significant advantage.

If you're a solo developer or small agency building client sites, think about what happens when a client asks you to hand off their project. A Sanity project requires the client to maintain a Sanity account and manage their plan. A Payload project requires the client to maintain hosting infrastructure. Which ongoing dependency is easier for your specific client to manage?

The honest answer

There's no lock-in-free option. There's only informed lock-in and uninformed lock-in. The teams that regret their CMS choice are almost never the ones who chose the "wrong" platform — they're the ones who didn't understand what they were trading away until it was too late to change course cheaply.

Read the pricing page carefully. Understand the metered limits. Look at the export tooling. Count the proprietary concepts in your codebase. Then make your choice with open eyes.

Let me know in the comments if you have questions about evaluating CMS lock-in for your specific project, and subscribe for more practical development guides.

Thanks, Matija