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Does a Shopify Theme Update Delete Your Customizations?

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Byte BlogJuly 14, 2025

A Shopify theme update, when approached correctly, is not a process to be feared. On the contrary, it is a critical step to improve your Shopify store's performance, security, and functionality.

The world of e-commerce demands constant adaptation to ever-changing dynamics. For your online store's core, your Shopify website, theme updates are vital to keep it current, secure, and high-performing. However, a common question puzzles many Shopify users: "Will a Shopify theme update erase my customizations?" Potential scenarios that may arise during the Shopify theme update process—such as data loss and, most importantly, the preservation of customizations—are among the key points users should pay close attention to. Gaining clarity on these aspects is essential for managing the process more effectively and boosting your store’s performance with confidence.

Why is a Shopify Theme Update Important?

Shopify theme update is more than just a new look. Themes are crucial components that form the infrastructure of your e-commerce site. Updates from Shopify or theme designers, which include new features, design improvements, and bug fixes, offer many advantages for your store's health:

  • Security Enhancements:The dangers in the cyber world are perpetually shifting and, in a sense, evolving. Theme updates on Shopify websites close potential security vulnerabilities, protecting your store and customer data.

  • Performance Optimization: Faster loading pages on Shopify websites mean a better user experience and, consequently, higher conversion rates. Up-to-date themes generally include performance improvements.

  • New and Functional Features: The Shopify platform and theme developers continuously offer new features. Thanks to updates, you can access these innovations and increase your store's functionality.

  • SEO Improvements: Search engine algorithms constantly change. Up-to-date themes on Shopify websites generally come with SEO-friendly configurations and coding standards, which can positively impact your search engine rankings.

  • Bug Fixes: Errors and compatibility issues from previous versions are resolved with updates. This ensures your Shopify store runs more smoothly.

For these reasons, regularly monitoring theme updates and applying them is of great importance for your Shopify website to remain competitive and offer a seamless experience.

Does a Shopify Theme Update Delete Your Customizations?

The answer to this question can be complex, but generally, yes, a Shopify theme update, by renewing the theme's core files and structure, can delete or overwrite some of the customizations you have made manually. However, this is not true for every customization and depends on specific conditions.

Which Files Are Deleted When Updating a Shopify Theme?

When Shopify themes are updated, changes made through manual interventions are particularly at risk. Here are the main types of files and changes that may be lost:

  • Code Changes: All code changes you have made directly within the theme files (e.g., .liquid files in sections, snippets, templates folders, or configuration files like config/settings_schema.json) are generally not included in the updated version. This means the theme's default structure is overwritten.

  • Files in the Assets Folder: Files located in the assets folder (e.g., theme.scss.liquid or theme.css, theme.js) do not save their previous versions. Changes you make to these files, such as custom CSS or JavaScript additions, may be lost during the update.

  • App-Made Changes: Some Shopify apps may automatically add code to your theme files during their installation. After a theme update, these integrations may break or disappear, which can affect the app's functionality.

On the other hand, theme settings (changes made from the Shopify admin panel, such as colors, fonts, layout options) and simple customizations made through the theme editor are generally preserved. However, it is important to remember that there can always be an exception.

Are Code Changes Lost After an Update?

Absolutely yes. If you have made direct code edits to your Shopify website's theme, these changes are at risk of being lost after an update. A theme update reloads the theme's original codebase and does not recognize the lines you have added or modified. This applies particularly to interventions made to add custom functionalities, modify existing code, or manipulate specific visual elements.

Therefore, it is critically important to back up all custom code you have added to your theme in a separate location before any theme update. After the update is complete, you will need to carefully integrate this code into the new theme version. This process may sometimes require re-arrangement due to compatibility issues.

Are Custom CSS Changes Deleted in a Theme Update?

Yes, your custom CSS (Cascading Style Sheets) changes can also be deleted during a theme update. The style files of Shopify themes are usually located in the assets folder and are named theme.scss.liquid or similar. Custom CSS rules you directly add or modify in these files are replaced with their original versions when the theme is updated.

For example, custom CSS codes you added to change the color, size, or position of an element will revert to the default theme style after the update. This can be annoying, especially for the fine details that form the visual identity of your Shopify website. Therefore, you should consider your custom CSS changes as part of your code backup strategy and plan to re-apply them after the update.

Ways to Protect Your Customizations During a Shopify Theme Update

Taking proactive steps is vital to minimize the risk of losing your customizations when updating your Shopify themes. Here is a detailed guide to help you:

How Can I Protect My Customizations After a Theme Update?

  1. Create a Theme Copy (Backup): This is the most important step you need to take. Create a copy of your current theme before updating. Go to Online Store > Themes in your Shopify admin panel, click the "Actions" menu next to your current theme, and select "Duplicate." This provides you with a rollback point and allows you to quickly revert to your old theme if any issues arise.

  2. Save and Document Code Changes: If you have made manual code changes to your theme, copy these changes to a separate text document or a code editor. Take detailed notes on which file, which lines, and what kind of changes you have made. This will guide you when transitioning to the new Shopify theme version.

  3. Check App Integrations: Check if the apps you use in your Shopify store are compatible with the new theme version. Review the app documentation or contact the app developer. Some apps may require reinstallation or re-configuration of their settings.

  4. Add the New Theme Version: When you see an update notification in your Shopify admin panel, click it to add the updated theme version to your theme library. This allows you to upload the new version as a separate draft without overwriting your current Shopify theme.

  5. Review and Test Customizations: Before publishing the new Shopify theme version, thoroughly test all your customizations (code changes, custom CSS, app integrations) to ensure they are working correctly. Especially check critical pages (product pages, cart, checkout) and functionalities. Make necessary adjustments.

  6. Publish: Once you are sure everything is working correctly and your Shopify store looks as you desire, you can publish the new theme version.

Following these steps will help you protect your customizations when updating your Shopify themes and minimize potential disruptions.

What Happens If an Unbacked-Up Customized Theme Is Updated?

If you update a customized Shopify theme without backing it up, you could face serious consequences. The most significant risk is that all manual code changes and custom CSS additions you have made will not be transferred to the new updated theme version. This can lead to significant losses in your Shopify store's visual identity and functionality.

For example, a specially designed banner, a JavaScript function you added, or the unique layout of a specific product page could completely disappear after the update. This situation results in a loss of both time and effort, as you may need to recreate all these customizations from scratch. Furthermore, the integration of some of your apps may break, which could disrupt your Shopify website's operational processes. In short, not backing up means putting your Shopify store's potential at risk.

Frequently Asked Questions About Shopify Theme Update Guide

There are some common questions that Shopify website owners have regarding theme updates. Here are the answers to these questions:

Is the Shopify Theme Update Automatic?

In Shopify, theme updates vary depending on the theme's source.

  • Shopify Theme Store Themes: If you downloaded your theme directly from the Shopify Theme Store, the platform may occasionally apply automatic updates for these themes, such as bug fixes or security patches. These types of updates generally do not change the theme's appearance or content. When major feature updates are available, you will receive a notification in your Shopify admin panel. You can click this notification to add the update to your Shopify theme library and apply it manually.

  • Third-Party Themes: Apart from free Shopify themes, automatic updates are not supported for themes purchased from a third-party designer outside the Shopify Theme Store. In this case, you need to contact your theme provider directly for updates and follow their instructions.

  • Old (Vintage) Themes: Very old Shopify themes (often referred to as "Vintage") are no longer updated. If you have such a Shopify theme, you should consider switching to a new theme to benefit from modern features and security improvements.

Therefore, it is important to regularly check and manually apply update steps to keep your Shopify theme up-to-date.

Strengthen Your Shopify Store by Keeping Your Theme Customizations Safe!

A Shopify theme update, when approached correctly, is not a process to be feared. On the contrary, it is a critical step to improve your Shopify store's performance, security, and functionality. Remember that in-depth customizations such as manual code changes and custom CSS additions carry the risk of being lost during an update. However, this is a risk that can be easily managed.

The key is always to be proactive: creating a copy of your Shopify theme before updating, documenting and backing up all custom code changes you have made, and thoroughly testing the new version before publishing. These simple yet effective steps ensure that your Shopify website remains up-to-date seamlessly, while guaranteeing that all your valuable customizations are safe.

If you need professional support when updating or customizing your Shopify themes, we at Byte would be happy to assist you. With our expertise in software development and e-commerce solutions, we can help you maximize your store's potential. For more information and support, you can visit our Shopify software development services page.