Shopify automatically generates your robots.txt file at yourstore.com/robots.txt. Unlike WordPress or static sites where you upload a file to your root directory, Shopify controls the base file and you can only append custom rules through your admin panel. To add custom directives, go to Online Store > Preferences in your Shopify admin, then scroll down to the Robots.txt section. Here you can insert additional rules that Shopify will append to their default directives. The default rules typically include allowing search engines to crawl your store while blocking admin areas, checkout pages, and cart URLs. Shopify's default robots.txt already handles most essential blocking: /admin, /checkout, /cart, /orders, /account, and various system URLs. This prevents duplicate content issues and keeps private pages out of search results. You'll also see sitemap references pointing to your XML sitemap. The custom rules box is where you add site-specific directives. Common additions include blocking staging content, filtering certain collections during testing, or disallowing specific crawlers. Use standard robots.txt syntax with User-agent and Disallow lines. Changes take effect immediately after saving. One critical limitation: you cannot override Shopify's base rules. If Shopify blocks something by default, your custom additions won't unblock it. You also can't completely replace the file like you would on a self-hosted platform. This is usually fine for 95% of stores, but it can be restrictive if you need granular crawl control. At Ottawa SEO, we typically only add custom rules when blocking problematic crawlers causing server load, or temporarily hiding product categories during major inventory changes. For most Shopify stores, the default file is well-structured and needs no modification. Always test your custom rules with Google Search Console's robots.txt tester after adding them. Mistakes here can accidentally block your entire store from indexing, and we've seen that happen when someone copies rules from another platform without adjusting the syntax.