WordPress Block Themes vs Classic Themes: Should You Switch in 2026?

If you've been developing WordPress websites for several years, there's a good chance you've spent a lot of time working with files like: header.php footer.php single.php page.php archive.php functions.php That's certainly where most of my WordPress development experience has been. But WordPress has been changing. With the Block Editor, Site Editor, block themes, patterns, and theme.json , WordPress now offers a very different approach to theme development. So I decided to take a closer look at the question: If you're already comfortable building classic WordPress themes, is it worth moving toward block themes in 2026? This isn't an article written from the perspective of someone who has spent years exclusively building block themes. Most of my own WordPress work has traditionally involved classic themes . Instead, I'm looking at block themes from the perspective of an experienced WordPress developer who is exploring how the platform is evolving—and where the newer approach fits alongside the architecture I've used extensively. Classic Themes vs Block Themes WordPress currently identifies two primary theme types: Classic themes Block themes According to the official WordPress Theme Developer Handbook, classic themes primarily use PHP, JavaScript, and CSS and can make extensive use of WordPress functions, hooks, and filters. Block themes, on the other hand, are built around block markup and HTML-based templates and allow users to edit more areas of the website through the Site Editor. A simplified comparison looks like this: Classic Theme Block Theme PHP templates HTML block templates single.php templates/single.html header.php parts/header.html footer.php parts/footer.html Template hierarchy Block-based templates Custom PHP logic Blocks + APIs + plugins Customizer / theme options Site Editor / Styles theme.json optional theme.json commonly used This doesn't mean classic themes are obsolete. They aren't. WordPress continues to maintain documentation for classic theme