Every few months someone asks me to "make their Shopify store headless" and what they picture is a theme swap. It is not a theme swap. It is a rebuild of the parts of the shop the customer sees, plus quietly taking ownership of a long list of things Shopify used to do for them without anyone noticing. I have done this enough times to know where the work actually lives, so here is the honest version.
Why people leave Shopify in the first place
Shopify is not a bad platform. Most stores should stay on it. The reasons people genuinely outgrow it are specific: the transaction fees on top of card fees, the monthly bill creeping up as you bolt on six or seven apps, hitting a wall on checkout customisation or business logic the platform will not let you change, or simply wanting to own the frontend instead of fighting Liquid and a theme. If your reason is "headless sounds modern", that is not a reason. Be honest with yourself about which of those actually applies before you spend the money.
What "headless" actually means here
Headless just means the frontend and the commerce backend are separated and talk over an API. There are two very different versions of this, and people conflate them. The first keeps Shopify as the backend and puts a custom frontend (I usually reach for Nuxt and Vue) in front of it using the Storefront API. The second moves off Shopify entirely onto another backend. The first is a frontend project. The second is a platform migration. They are not the same size of job, and the word "headless" hides that difference, so pin down which one you are buying.
The frontend is the easy part
Rebuilding the product page, the collection pages, cart, search and account screens in Nuxt is real work, but it is known work with a known shape. You design it, you build it, you test the queries, you ship only the data each page needs. If the whole project were just this, it would be predictable. It is the stuff around the edges that catches people out.
The things Shopify did for free that you now own
Checkout is the big one. Shopify's checkout is locked down, and that is deliberate because it is where their fraud handling, tax, shipping rates and conversion work lives. If you keep Shopify as the backend you usually keep their checkout, which is the sensible choice. If you move off Shopify, you are now responsible for the checkout, the payment integration (Stripe or similar), tax calculation, shipping rate logic, order confirmation emails and discount codes. None of that is impossible. All of it is work you did not have before, and some of it is work you really do not want to get wrong.
Then there are the apps. Every app in your Shopify admin is a feature you are currently renting: reviews, subscriptions, a search engine, loyalty points, a back-in-stock alert. Going headless does not delete the need for any of those. It just turns each one into something you either rebuild, replace with a third-party API, or decide you can live without. I make clients list every app they pay for before we start, because that list is usually longer than they remember.
Data migration is where the timeline slips
Products, variants, images, customers and order history all have to move, and the messy reality of a few years of real catalogue data is always worse than the spreadsheet suggests. Two things bite people every time. URL structure changes, so without a redirect map you throw away your search rankings on day one. And customer passwords do not migrate, because they are hashed, so returning customers have to reset them and you need a plan to tell them why. Budget real time for this. It is the part that always runs long.
Do not throw your SEO away
The whole selling point of going headless is speed, so the one outcome you cannot accept is launching faster but ranking worse. Map every old URL to its new home with 301 redirects, keep your structured data, and actually measure Core Web Vitals before and after rather than assuming the new stack is quicker. I have seen "fast" headless rebuilds ship more JavaScript than the Shopify theme they replaced. Measure it, do not trust the brochure, including mine.
So is it worth doing?
For a lot of small stores, no. Stay on Shopify, spend the money on products and marketing, and revisit it when you have actually hit a wall. It is worth it when you have genuinely outgrown the constraints, have custom requirements the platform fights you on, and the fee savings or the control justify both the build and the ongoing maintenance, because you are taking on responsibility you did not have before. Going headless is not a free upgrade. It is a trade: more control and more speed in exchange for owning more of the machine.
If you are weighing it up, I have written more about owning your ecommerce platform and what that really costs, and the Shopify to headless migration page goes through how I scope one of these. Either way, go in knowing what you are signing up for.