How to change Shopify themes without breaking your store

5 min read
created Apr 04 2018
How to change Shopify themes without breaking your store

So you're ready to give your Shopify store a fresh new look by switching to a new Shopify theme. Or perhaps you are just thinking about it.

Well before you pull the trigger and change your Shopify theme there are a few things you should consider.

Flair product badges customer MJ recently wrote in to ask me about changing her theme:

We're in the process of changing the theme for our store. We haven't yet published the new theme to our website but wanted to check with you to see if there is anything we need to do to make the migration work smoothly with your app.

Shopify makes it really easy to swap out your theme. But if you have any theme customizations, including Shopify apps that add functionality to your store, there may be a bit of work to do before you make the switch.

In today's post i'd like to share a few tips to make it easier for you to change to a new Shopify theme without breaking your store.

We'll discuss:

  • Things you don't need to worry about
  • Things you should should watch out for
  • Changes made via Customize
  • Manual theme changes
  • Shopify app changes
  • Previewing your new theme safely

Things you don't need to worry about

When you are changing your Shopify theme to a new one, much of your shop's data will be automatically transferred over to the new theme. This is because Shopify stores this data outside of the theme which means the new theme can just reuse the same data.

Here is a list of the things you don't need to worry about when switching to a new Shopify theme:

  • Product data
  • Collections
  • Blog posts
  • Pages (such as About Us)
  • Navigation

Things you should should watch out for

So what types of things do you have to watch out for when switching themes? For the most part, the list of things you need to watch out for includes any changes made inside your existing theme itself.

This includes:

  • Changes you make when you Customize your theme
  • Manual changes you made to any of your theme files such as custom CSS, Images, or HTML / Liquid
  • Theme changes made by installed Shopify apps

Let's take a look at each of these below to discuss how you can review and possibly migrate these changes to your new theme.

Changes made via Customize

If you made any changes via the Customize tool in your theme, these changes will not be carried over to your new theme.

These types of changes can be broken down into two categories:

  • Look and feel changes
  • Content changes

Look and feel changes

Look and feel changes are things such as how many items to display per row in your collections or whether to show different product badges.

In general, look and feel changes are not as important to review since they should be handled when you Customize your new theme.

Content changes

Content changes include anything that involves custom content being shown to your customers in your shop. This typically involves new sections on your Shopify Frontpage such as featured collections or custom welcome text.

For content changes, you will need to decide if you want to move them over to your new theme or if you are going to try something different. You should be able to add a similar content using your new theme's Customize tool.

Manual theme changes

Manual theme changes involve any changes you may have made within the theme itself. This includes modifying any of the following types of files within your theme:

  • Liquid
  • HTML
  • CSS
  • Javascript
  • Images

Changes like these can cover a wide range of functionality. You can still break these down based on whether they are primarily look and feel based or involve custom content like we did in the Customize section above.

You'll need to assess each of your customizations in turn to decide if it is worth bringing them over. Often times look and feel customizations may not be needed in your new theme since the new theme displays things completely differently.

If you have some heavy customizations to add advanced functionality you may need to use a bit more care when moving them over to your new theme.

Shopify app changes

Many Shopify apps may also stop working properly, or in some case even impact your Shopify store, when you change your Shopify theme.

Why is this?

You see, Shopify apps that add functionality in a way that is visible to your customers need to interact with your theme files. In some cases, you may need to modify your new theme files to add support for the app. In other cases, the app may automatically install itself into your new theme.

As a result, when you switch to a new Shopify theme, the change in theme files can result in some of your apps no longer working properly.

My app Flair uses a simple Liquid snippet to add product badges to a Shopify store. So when MJ switched her theme, she just had to add the Flair snippet where she wanted the product badges to show in her new theme.

When switching Shopify themes, be sure to review your Shopify apps to make sure they continue to work in your new theme. Pay particular attention to any apps that are customer-facing. If your apps aren't working in your new theme, you should reach out to your app developer and see if there are any special installation steps required.

Previewing your new theme safely

Regardless of which changes you need to make to change to your new theme, you can do this in a safe way without breaking your site.

The way to make these changes safely is to install your new theme but don't publish it.

Then you can safely make your changes to the new unpublished theme, and preview these changes until you are satisfied. This will make sure your current theme and shop keep running smoothly throughout the entire process.

You can also checkout my guide on how to safely make changes to your Shopify theme for more details.

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When changing your Shopify theme, you should plan reviewing any customizations you made to your current theme before making the switch.

Any customizations you made via the theme Customize tool or to specific theme files may need to be manually migrated to your new theme.

You should also be sure to verify your Shopify apps work properly in your new theme before you publish it to your live store.

You can also safely verify your new theme before you publish it by using the built-in Shopify theme preview tool.