Should a marketing site use headless WordPress or Sanity?

Headless WordPress is the lower-risk path because content stays where it is and editors keep wp-admin, and the cost is two systems to maintain. Sanity gives a cleaner content model and previews, and the cost is a full content migration.

What are the SEO risks of moving to a headless CMS?

The risk sits in changed URLs, dropped pages, rewritten copy that no longer matches the query it ranked for, and slower templates. A redirect map, copy that still answers the original query and a speed check before launch cover all four.

How much does a headless CMS migration cost?

The main cost is developer time, and it scales with page count, content model complexity and how many editors need training. For most marketing sites, hosting and CMS fees are small next to that.

How do editors work and preview changes in a headless CMS?

Editors work in Sanity Studio, or stay in wp-admin if WordPress remains the backend, and previews are set up as part of the front-end build. Training time depends on the team.

Should we keep WordPress running during the migration?

Run both until the new front end is tested, keep the old site on its URLs until the redirects are verified, and switch DNS on a day when someone is watching Search Console.

WordPress to Headless CMS: Sanity and Next.js

Moving off WordPress to a headless setup suits some B2B teams and is an expensive detour for others. This post covers who should move, what each part of the stack does, and what the migration involves.

TL;DR

Migrate when WordPress's page-based structure blocks your editors, plugin upkeep and security work take real hours every month, or the same content has to feed more than one site. Stay when the site is small, runs WooCommerce, or the editors are happy in Gutenberg.
Keeping wp-admin and rebuilding only the front end in Next.js is the lowest-risk first step, and a full move to Sanity adds a content migration on top.
Sanity is the CMS, Next.js is the framework and Vercel is the host, so each one is a separate decision.
Protect rankings with a URL inventory, a 301 for every URL that changes and a speed check against the old site before launch.
The main cost is developer time, which scales with page count, content model complexity and how many editors need training, and hosting and CMS fees are small next to it.
A headless build with us usually takes 4 weeks or more, from content model to launch.

The WordPress logo with an arrow pointing to the Sanity, Next.js and Vercel logos

What headless means

In a headless setup the CMS stores content and serves it through an API, and a separate front end builds the pages visitors see. With WordPress that means editors keep working in wp-admin while a Next.js site fetches the content, or the content moves to a CMS like Sanity and WordPress goes away.

Sanity is the CMS, Next.js or Astro is the framework and Vercel is the host, so each layer is a separate decision.

When to stay on WordPress

Stay when the site is a few dozen pages and a plugin or two covers what you need, when WooCommerce sits at the centre of the business, when a large editing team is deeply used to Gutenberg, or when you depend on a plugin with no equivalent elsewhere. WordPress user management, multisite and membership tools take real effort to rebuild in a custom stack, and for these sites a caching plugin and good hosting are usually the cheaper fix.

When to migrate

Four signals point toward headless.

The editing team waits on developers to publish new page layouts, or the content model is squeezed into posts and pages when it needs integrations, case studies and customers as separate linked types.

Plugin updates and security patches take real hours every month, and a bad update has broken the site before.

The same content has to reach a web app, a newsletter, docs or AI tools as well as the website. Structured content also helps with answer engines, which we cover in AEO for SaaS.

The front end has performance or design requirements that themes and page builders cannot meet.

If none of these apply, a rebuild in Webflow or Framer is usually the lighter move, and our Webflow vs WordPress post covers that path.

Signal	Points to
A few dozen pages, and a plugin or two covers what you need	Stay on WordPress
WooCommerce sits at the centre of the business	Stay on WordPress
A large editing team deeply used to Gutenberg	Stay on WordPress
You depend on a plugin with no equivalent elsewhere	Stay on WordPress
Editors wait on developers to publish new page layouts	Headless
Plugin updates and security patches take real hours every month	Headless
The same content has to reach a web app, newsletter, docs or AI tools	Headless
Performance or design needs that themes and page builders can’t meet	Headless

Sanity, Next.js, Astro and Vercel

Sanity

Sanity holds content as structured data that you define yourself. Case studies, integrations, pricing tiers and authors become their own types with their own fields, and editors can preview the page as they edit it. Rich text is stored as Portable Text, which converts cleanly to any front end, and the image pipeline handles crops and hotspots. Plan limits change, so check them before you budget.

Next.js

Next.js is the most common framework for headless front ends. It supports incremental static regeneration, so pages are served pre-built and refresh when content changes, and its large ecosystem means most integration problems already have an answer.

Astro

Astro suits content-led marketing sites with little interactivity, since it ships very little JavaScript to the browser by default. Pick Astro when the site is mostly pages and the product app lives elsewhere, and pick Next.js when the site shares components or logic with a React app.

Vercel

Vercel is the natural host for Next.js, with preview deployments on every branch, instant rollbacks and edge delivery built in. The Hobby plan is free and Pro is priced per seat, so check current pricing and count how many people need access.

What a migration involves

Start with a URL inventory. Export every page, pull Search Console and backlink data by URL, and decide which URLs stay identical.

Model the content in Sanity next, so each WordPress post type and custom field has a destination type.

Then write an import script that reads the WordPress REST API, turns posts into Sanity documents and uploads the images, and test it on a copy before touching real content.

Rebuild the templates in Next.js or Astro, match the heading structure and metadata of the pages that rank, and set up previews for the editors.

Write a 301 redirect for every URL that changes and check that each one points to its closest new page, then compare speed against the old site before launch.

After launch, submit the new sitemap, watch 404s and indexing in Search Console, and track conversions for the first weeks.

How we set up a headless build

Sanity is our usual pick for the CMS, connected with next-sanity on Next.js and the official @sanity/astro integration on Astro. We model the content with you, set up previews, connect publishing to the site, and agree who edits what before the build starts.

Editors often work in Sanity Studio on your own domain, for example at /admin. On Next.js, published changes can appear live without a rebuild. On a static Astro site, a publish triggers a rebuild that usually takes a minute or two.

DesignMe handles website migrations for funded B2B SaaS and AI companies. If you are weighing a move off WordPress, send us the site and we will tell you which route fits:

designme.agency/intro