WordPress Block Template Not Applying? Start With the Database

Your template file is almost certainly being ignored because a copy in the database is winning. The moment you open a template in the Site Editor and press Save, WordPress writes a wp_template post record, and from then on that record is served instead of the .html file in your theme folder — so every edit you make to the file afterwards is invisible on the front end. Clearing that record is the fix, and it is the first thing to check before you touch the hierarchy, the filename, or the cache.

Confirm the database copy exists

Go to Appearance → Editor → Templates. Any template WordPress is serving from the database is flagged in the list — depending on your WordPress version the badge reads “Customized” or the template appears under a “Customized” filter. That badge is the whole answer. If it is there, your file is not being used.

You can check the same thing from the command line, which is faster and works even when the Site Editor is misbehaving:

wp post list --post_type=wp_template --fields=ID,post_name,post_status,post_title
wp post list --post_type=wp_template_part --fields=ID,post_name,post_status,post_title

Each row is a database override. The post_name matches the template slug, so a row named single is shadowing templates/single.html.

One detail that trips people up: these records are tied to a theme through a taxonomy term, not through a path. If you rename your theme’s folder, the saved templates stay in the database but stop matching the active theme, and the site abruptly falls back to files. That looks like “my customizations vanished” rather than “my file is ignored” — same mechanism, opposite symptom.

Clear it

In the Site Editor, open the template’s options menu (the three dots next to it) and choose Clear customizations — some versions label it Reset. That deletes the database record and control returns to the file on disk.

If the menu offers Delete instead of Clear customizations or Reset, that template exists only in the database and has no file behind it. Deleting it removes the template entirely and WordPress falls back down the hierarchy.

From WP-CLI, using an ID from the list above:

wp post delete 482 --force

Be honest with yourself about the cost here: clearing customizations permanently discards whatever you built in the Site Editor for that template, and it cannot be undone. If the Site Editor version has real work in it, copy the block markup out first — open the template in the editor, switch to the code view, and paste the result into your .html file. That way the file becomes the source of truth and nothing is lost.

How WordPress picks a template

Block themes use the same hierarchy logic as classic themes, just with .html files in templates/ instead of .php files in the theme root. WordPress walks from most specific to least specific and uses the first file that exists.

Viewing	Checked in this order
A single post	single-post-{slug}.html → single-post.html → single.html → singular.html → index.html
A page	page-{slug}.html → page-{id}.html → page.html → singular.html → index.html
A category archive	category-{slug}.html → category-{id}.html → category.html → archive.html → index.html
A custom post type	single-{post-type}.html → single.html → singular.html → index.html
The 404 page	404.html → index.html

Two things override this entirely. First, the database record described above. Second, a template assigned directly to a post or page — open the post editor, look for the Template panel in the sidebar, and check whether something specific is selected there. An explicit assignment beats the hierarchy every time, and it is invisible unless you go looking for it.

Slug-based templates are fragile in a way that is worth internalizing. page-about.html matches only while the page’s slug is about. Rename the page to about-us and the template stops applying with no warning and no error.

Template versus template part

A template renders an entire view and is selected by the hierarchy. A template part is a fragment — header, footer, sidebar — that templates pull in. Parts live in parts/, templates live in templates/, and they are stored separately in the database as wp_template_part records.

The common confusion: you edit the header, and the change shows up on pages you did not intend to touch. That is correct behaviour. One part is shared by every template that includes it. If you want a different header on one template, you need a second part file and a template that references it — editing the shared one will never give you per-template variation.

The reverse also happens. You put a full page layout into parts/ and wonder why the hierarchy never picks it up. Parts are not candidates in the hierarchy at all; nothing will ever route to them directly.

File naming and location

Check these before assuming anything more exotic:

• The folder is templates/, plural, at the theme root. Not template/, not block-templates/. block-templates/ was the correct name during the Gutenberg-plugin era before block themes landed in core, and plenty of tutorials still show it — it does not work in current WordPress.
• Template parts go in parts/, not template-parts/ (which is the classic-theme convention for PHP partials).
• The extension is .html. A .php file in templates/ is ignored.
• Filenames are lowercase and use hyphens. single-Post.html or single_post.html will not match. On a case-insensitive filesystem such as macOS this works locally and breaks on a Linux server — a classic “works on my machine” failure.
• templates/index.html must exist. Without it, WordPress does not classify the theme as a block theme and the Site Editor may not appear at all.
• If you are working in a child theme, its templates take priority over the parent’s. A leftover file in the child theme will quietly beat the parent file you are editing.

Custom templates that should be selectable in the post editor also need declaring in theme.json under customTemplates, with the file’s base name, a human-readable title, and the post types it applies to. Without that entry the file exists but never appears in the Template panel.

Caching — check it last

Caching is real but it is the least likely cause, and reaching for it first is how people lose an afternoon.

Purge your page cache and, if you run a persistent object cache such as Redis or Memcached, flush that too — template resolution results can be held there. Then reload with the browser cache bypassed.

What will not help: clearing OPcache. Block templates are .html files and are never compiled by PHP, so OPcache has nothing to do with them. If flushing OPcache appeared to fix this for you once, something else changed at the same time.

Still stuck?

With no database record, a correct filename, no explicit template assignment on the post, and caches already purged, look at plugins. Anything that filters template resolution — a page builder, a membership plugin, a multilingual plugin, an LMS — can substitute its own template late in the request. Switch to a default block theme and test with plugins disabled, then re-enable one at a time.

And if the template is applying but renders empty, that is a different problem: check that the block markup in the file is valid, since a malformed block comment can cause the editor to strip content silently rather than throw an error.