--- title: Readonly Property Defaults in PHP 8.6: A Four-Year-Old... description: PHP 8.6 removes a four-year-old restriction and allows readonly properties to declare default values. This makes readonly properties usable in interfaces and... canonical: https://daily.dev/posts/readonly-property-defaults-in-php-8-6-a-four-year-old-restriction-finally-lifts-gohj3ferj twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Readonly Property Defaults in PHP 8.6: A Four-Year-Old Restriction Finally Lifts | daily.dev og:description: PHP 8.6 removes a four-year-old restriction and allows readonly properties to declare default values. This makes readonly properties usable in interfaces and... og:url: https://daily.dev/posts/readonly-property-defaults-in-php-8-6-a-four-year-old-restriction-finally-lifts-gohj3ferj og:image: https://api.daily.dev/og/posts/GOhj3Ferj.png og:image:alt: Readonly Property Defaults in PHP 8.6: A Four-Year-Old Restriction Finally Lifts og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Readonly Property Defaults in PHP 8.6: A Four-Year-Old Restriction Finally Lifts **[PHP Architect](https://daily.dev/sources/phparchitect)** · [@shocm](https://daily.dev/shocm) · 1 min read · 0 upvotes · 0 comments ## Summary PHP 8.6 removes a four-year-old restriction and allows readonly properties to declare default values. This makes readonly properties usable in interfaces and simplifies patterns that previously required constructor promotion workarounds. The change also introduces edge cases developers should be aware of when adopting it. ## Content PHP 8.6 lets readonly properties declare default values. Here is what changed, why interface properties made it worthwhile, and the edge cases to watch. https://shocm.me/posts/2026-08-30-php-86-readonly-property-defaults/ ## Similar posts on daily.dev - [\[RFC\] Readonly Property Defaults](https://daily.dev/posts/rfc-readonly-property-defaults-wdsrbpxad) · externals.io · 0 upvotes · 0 comments - [What's new in PHP 8.6](https://daily.dev/posts/what-s-new-in-php-8-6-eixar55ou) · stitcher.io · 103 upvotes · 7 comments --- Tags: [#general-programming](https://daily.dev/tags/general-programming), [#php](https://daily.dev/tags/php) [View this post on daily.dev](https://daily.dev/posts/readonly-property-defaults-in-php-8-6-a-four-year-old-restriction-finally-lifts-gohj3ferj) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"DiscussionForumPosting","mainEntityOfPage":"https://daily.dev/posts/readonly-property-defaults-in-php-8-6-a-four-year-old-restriction-finally-lifts-gohj3ferj","headline":"Readonly Property Defaults in PHP 8.6: A Four-Year-Old Restriction Finally Lifts","text":"PHP 8.6 removes a four-year-old restriction and allows readonly properties to declare default values. 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