OpenCart vs Laravel: You Already Own a PHP Application
This is not a choice between a hosted product and a custom build. OpenCart runs on your own server, in your own PHP. The question is narrower, and it is about where your business rules live.
The comparison pages for this usually lump OpenCart in with hosted platforms and argue about control and ownership. That argument does not apply here. You already have control. OpenCart is PHP on your own server, your database, your files, no per-order fee, and nobody can change the terms underneath you.
So the honest version of this question is narrower: you have a PHP application, and you are asking whether it is still the right one for what the business now does.
What OpenCart is genuinely good at
Worth saying plainly, because it gets left out.
A catalogue with options and variants, a cart, a checkout, tax and shipping rules, a multi-store setup, an admin a small team can operate without training. It runs on inexpensive hosting, it has been deployed hundreds of thousands of times, and the extension marketplace covers most of what a growing store asks for.
If that description still matches your store, stay. Replacing a working cart with a custom application is a large bill for a result that looks similar to your customers.
Where the question actually starts
Not at traffic, and not at catalogue size. It starts when the rules you need stop being about the catalogue.
An extension is the natural shape for anything a cart already has a concept of: a pricing rule, a shipping method, a payment provider, a field on a product. That is what the extension model is for and it works.
The shape changes when the rule is about something else. A quotation that becomes an order after approval. A fulfilment process with states that operations staff move things through. Customer-specific contract pricing with its own history. Stock that lives in an ERP and has to stay agreed with it. Subscriptions and proration.
None of those are things a cart was built to hold, and each one implemented as an extension has to reach into parts of the system not designed for it. That is where the cost starts, and it is a cost of fit rather than a fault.
The modification question, honestly
The thing worth measuring before anything else is how far your installation has moved from a stock one.
OpenCart's extension model has historically let extensions alter core behaviour directly. That is what made it flexible and easy to extend, and it is also why two stores on the same version can be in very different states. Some are close to stock and upgrade cleanly. Some have a decade of modifications, several of them touching the same files, installed by people who are no longer available.
Read that before deciding anything. It is a day of work and it changes the arithmetic completely, because a store that upgrades cleanly has a cheap option that a heavily modified one does not. It is the same reading an audit does, applied to a different codebase.
What a Laravel application changes, and what it does not
It changes where the rules live. A service layer, a schema with constraints on it, migrations, a test suite, and a queue for the work that should not happen inside a request. If the business logic is the product, that is what the framework is for.
It does not change your hosting story for the better on its own, and it does not give you a catalogue, a cart or a checkout. Those you rebuild. That is the honest cost and it is the reason we start by asking whether the fit problem is real or whether two extensions are doing something awkward.
How a move actually runs
Route by route, with both systems live, which is the approach rather than the exception.
OpenCart keeps serving the storefront while the new application takes over one group of routes at a time. One system owns the order at any given moment, and which one that is gets written down before anything moves. The URL map comes first, because collection and product URLs are what earned your traffic and a redirect written in the last week is a redirect written too late.
And the order model goes in before the storefront. The storefront is the cheapest part to change later.
If the store is on a rented platform rather than your own server, the ownership argument that does not apply here becomes the whole argument, and that is a different page.
