Block themes have been around since WordPress 5.9 dropped Full Site Editing in 2022, and every year the question comes back: should you still build classic PHP themes, or is everyone supposed to be on block themes by now? After four years of FSE evolution and shipping both styles for clients, here is my honest take going into 2026.
What changed in the last twelve months
FSE matured. The Site Editor in 6.7 and 6.8 finally feels like a tool a non-developer can use without breaking things. Style variations, font library, pattern overrides, and Data Views in 6.6 closed real gaps that made block themes painful for anything beyond a basic blog. The block bindings API now lets you wire custom fields directly into block content without writing a custom block, which used to be a significant reason to stay classic.
That said, the gap between what you can build in a block theme and what you can build in a classic theme is still real. It is just narrower than it was.
When a classic theme still wins
If the project requires complex custom post types with intricate template logic, deeply custom queries, or integration with third-party APIs that need PHP-side processing, a classic theme is still the cleaner build. You write PHP, you control everything, and you do not fight the editor. For agency work where the client will never touch the editor and the dev team owns every change, classic themes are honestly fine.
Performance also tilts classic for custom-built themes. A custom classic theme with no page builder can ship under 30KB of CSS and almost no JavaScript. Block themes ship the block library CSS and the editor runtime even on the front-end if you are not careful, though you can dequeue most of it.
When a block theme is the right call
If the client wants to manage their own site after launch (change colors, edit headers, swap layouts, build new pages from patterns), block themes are now the better choice. The Site Editor is good enough that a small business owner can actually use it without breaking the design, especially with locked patterns and theme.json constraints.
For content-heavy publishers, block themes win on iteration speed. Marketing teams can spin up new landing pages in minutes from saved patterns instead of waiting on a developer.
The hybrid approach
A pattern I have been shipping more often is a hybrid: a classic theme that registers blocks and patterns, supports the block editor fully on individual posts and pages, but uses PHP templates for the structural pages (header, footer, archives, single templates). You get the developer control of classic templates plus the editor flexibility for content. It is not officially called “hybrid” anywhere, but it works.
Practical advice for 2026
- New small business sites the owner will manage: block theme
- Custom application-like sites with heavy PHP logic: classic or hybrid
- Content publishers with editorial teams: block theme with locked patterns
- WooCommerce stores: still classic for now, FSE WooCommerce support is improving but not there for complex stores
- Agency client work where you maintain it: whatever you are fastest in
The honest answer is that the right choice depends on who maintains the site after launch. Build for the maintainer, not for the trend.
Not sure which one fits your project?
Tell me what you’re building and who will maintain it after launch, and I’ll tell you honestly which architecture fits. Book a free 30-minute call, or see how I approach custom development.
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