SaaS vs Open Source Ecommerce Platforms: How to Choose in 2026

Choosing between a SaaS ecommerce platform and an open source ecommerce platform is the first real decision in any new build or replatform, and it shapes everything after it: what your checkout can do, how your ERP connects, who keeps the store secure, and what you pay every year. If you want a fast answer for your own business, take our SaaS vs open source ecommerce quiz. It takes about four minutes and explains the reasoning behind its result.

This guide covers the ground underneath that answer. It explains what each model is, where Shopify Plus, BigCommerce, Magento Open Source and Adobe Commerce sit, how the costs really compare, and which signals point one way or the other. It comes from the platform decisions we work through with merchants every week, including during ecommerce replatforming projects, where getting this choice right matters most.

What is a SaaS ecommerce platform?

A SaaS ecommerce platform (software as a service) is ecommerce software you subscribe to instead of owning. The provider hosts the store, keeps it secure, handles uptime and releases upgrades for you. You manage products, content and marketing in an admin, and you add features with apps from the platform's marketplace.

The best-known SaaS ecommerce platforms for growing and enterprise brands are:

• Shopify and Shopify Plus. One of the largest SaaS ecommerce ecosystems, with a huge app store, a fast checkout and strong tools for direct-to-consumer brands. Shopify Plus adds enterprise features such as B2B, checkout extensibility and automation.
• BigCommerce. A SaaS platform that markets itself as "Open SaaS": hosted like any SaaS, but built around open APIs so you can connect your own systems. It has native B2B features and is often more flexible at checkout.
• Salesforce Commerce Cloud. An enterprise SaaS platform used by large retail brands, usually alongside the wider Salesforce suite.

Ecommerce SaaS is multi-tenant: many stores run on the same core software. That's what makes it affordable to run and quick to launch, and it's also why you can't change the core. You customize through themes, apps and the APIs the platform chooses to expose.

What is an open source ecommerce platform?

An open source ecommerce platform gives you the full source code. You install it on hosting you control, and you or your development partner can change how anything works, from the database to the checkout. There's no subscription to the software itself, but you take on hosting, security, upgrades and development.

The open source and code-owned options merchants ask us about most are:

• Magento Open Source. The free, open source edition of Magento, released under the OSL 3.0 license. It's one of the most widely used open source commerce platforms for mid-market and B2B stores, with a large developer and extension ecosystem.
• Adobe Commerce. The paid, licensed edition built on the same Magento codebase. You still get the full code, plus enterprise B2B features, Adobe's cloud hosting options and support from Adobe. Strictly speaking it isn't open source, because it's sold under a commercial license, but it works like open source in the way that matters most here: you own and control the code.
• Other open source commerce frameworks, such as Spree Commerce, Sylius and PrestaShop. These are used less often for large catalogs and complex B2B than Magento, but you'll see them in specialist builds.

Open source ecommerce is sometimes called self-hosted ecommerce, because the store runs on servers you choose rather than the provider's.

Is Shopify open source? Is BigCommerce? Is Magento?

These are some of the most common questions we hear, so here are the straight answers.

• Is Shopify open source? No. Shopify is SaaS. You can build custom themes, private apps and headless storefronts, and Shopify's Hydrogen framework for headless builds is open source, but the core platform is not. You can't change how it works under the hood or host it yourself.
• Is BigCommerce open source? No. BigCommerce is SaaS. "Open SaaS" describes its API-first approach, not its license.
• Is Magento open source? Yes. Magento Open Source is free to download, modify and host.
• Is Adobe Commerce open source? Not by license. It's a paid edition of Magento, but you still receive and control the full codebase.
• Is Salesforce Commerce Cloud open source? No. It's an enterprise SaaS platform.

SaaS vs open source ecommerce: side by side

Which costs less: SaaS or open source?

This is the question behind most platform decisions, and the honest answer is that the license is the smallest part of the cost. What matters is total cost of ownership over three to five years.

Where the money goes on a SaaS ecommerce platform:

• The subscription, which usually rises as you move up plans or as your sales grow.
• App fees. Every feature you add through an app is another monthly charge, and stores with dozens of apps often spend more on apps than they expect.
• Payment fees. Shopify, for example, adds a fee on orders paid through a payment processor other than Shopify Payments. If you need to keep your own merchant account, check the current rates in our Shopify Plus pricing breakdown before you commit.
• Development for custom themes, apps and integrations.

Where the money goes on an open source ecommerce platform:

• Hosting, including the infrastructure to handle your peak traffic.
• Development and maintenance, including security patches, extension updates and planned upgrades.
• Licensing, if you choose Adobe Commerce, which Adobe prices based on your sales volume. Our Adobe Commerce pricing guide explains how that works.
• Extensions for features that aren't built in.

"Free" open source is rarely the cheapest option once hosting and upkeep are counted, and SaaS is rarely the cheapest option once a complex business has added the apps and workarounds it needs. The cheapest platform is the one that fits your business without fighting it. When a SaaS store needs constant workarounds, or an open source store has nobody to maintain it, the bill goes up either way.

When a SaaS ecommerce platform is the right choice

SaaS is usually the right call when most of these are true:

• You sell mainly direct to consumers, or your B2B needs are straightforward.
• Your checkout is standard, with no split shipments, approvals or unusual payment flows.
• Your pricing is simple, with a handful of price lists rather than pricing per customer.
• Your systems are common ones, such as NetSuite or QuickBooks, with good off-the-shelf connectors.
• You don't have developers in-house and would rather not own hosting, security and upgrades.
• You want to launch quickly and prefer predictable monthly costs.

If that sounds like your business, our Shopify Plus agency and BigCommerce agency teams build and support SaaS stores every day.

When an open source ecommerce platform is the right choice

Open source earns its extra responsibility when your business needs things a hosted platform can't do cleanly:

• Dealers, distributors or suppliers connect through their own systems, for example sending orders through custom APIs or feeding your inventory in real time.
• Your checkout needs to bend, with split carts, shipments from several warehouses, approval steps or document uploads.
• Your B2B pricing is complex, with contract pricing, customer-specific catalogs or hundreds of accounts with their own price lists.
• Your ERP is custom or older, or sits behind your company firewall.
• You have rules about where data lives or who can access it, such as ITAR, government contracts or data that must stay in one country.
• You sell restricted products, such as CBD or firearms parts, where a hosted platform's policies are a business risk.
• You run several brands or regions from one back office.

For these businesses, our Magento agency and Adobe Commerce agency teams build, host and maintain open source stores, so you get the control without needing a large in-house team.

Where headless and composable commerce fit

Headless commerce separates the storefront your customers see from the commerce engine that runs products, carts and orders. Composable commerce takes the idea further, assembling the stack from separate services for search, content, checkout and more.

Neither replaces the SaaS or open source decision. Headless works on both: Shopify Plus and BigCommerce both support headless storefronts, and so does Adobe Commerce. What headless changes is how much frontend freedom you have and how much more you need to build and maintain. It tends to pay off for brands with heavy content, several storefronts or very specific frontend experiences. A headless commerce agency can tell you whether that extra flexibility is worth it for your team, and our guide to headless commerce in 2026 goes deeper.

SaaS vs open source for B2B ecommerce

B2B is where the decision gets most interesting. SaaS B2B features have improved a lot. Shopify Plus and BigCommerce now handle company accounts, price lists, net terms and purchase orders, which covers a large share of wholesale businesses.

The line usually falls on scale and complexity. Open source B2B ecommerce platforms such as Adobe Commerce pull ahead when you have hundreds or thousands of accounts with their own catalogs, sales reps ordering on behalf of customers, quote-to-order workflows, or ERP-driven pricing that has to be exact. Our comparison of B2B ecommerce platforms and our guide to what B2B buyers expect from ordering portals cover this in more detail.

Can you switch later?

Yes, and plenty of merchants do, in both directions. Brands move from Magento to Shopify Plus to simplify, and others move from Shopify to Adobe Commerce when their integrations and B2B needs outgrow apps. A replatform means moving products, customers and order history, rebuilding integrations, and protecting your search rankings with redirects. Our ecommerce migration checklist covers what to watch in the first year after a move.

The best way to avoid an expensive switch is to choose with the next three to five years in mind, not just the next launch.

A 10-point checklist for choosing your platform

Answer these honestly and the right direction usually becomes clear:

1. Who do you sell to: consumers, businesses or both?
2. Do partners connect to your store through their own systems or APIs?
3. What does your checkout need beyond a standard cart and payment?
4. How many pricing rules and B2B catalogs do you manage?
5. Which ERP, PIM, warehouse and CRM systems does the store need to talk to?
6. Who will build and maintain the store: your team or a partner?
7. How hands-on do you want to be with hosting, code and releases?
8. How many stores, brands and regions do you run?
9. Do you sell restricted products, or have rules about where your data lives?
10. How do you prefer to pay: month to month, annually, or by owning the software?

Frequently asked questions

What is the difference between SaaS and open source ecommerce?

A SaaS ecommerce platform is hosted and maintained by the provider, and you pay a subscription to use it. An open source ecommerce platform gives you the source code to host and change yourself, so you get full control but take on hosting, security and upgrades.

Is SaaS or open source better for ecommerce?

Neither is better for everyone. SaaS suits businesses with standard needs that want speed and low maintenance. Open source suits businesses with custom integrations, complex B2B pricing, unusual checkouts or strict data rules, and the developers or partner to run it.

Is Shopify a SaaS platform?

Yes. Shopify and Shopify Plus are SaaS ecommerce platforms. Shopify hosts the store, handles security and upgrades, and you extend it with themes and apps.

Is Magento free?

Magento Open Source is free to download and use under the OSL 3.0 license. You still pay for hosting, development and maintenance. Adobe Commerce, the enterprise edition, requires a paid license.

Is open source ecommerce cheaper than SaaS?

Not automatically. There is no license fee for Magento Open Source, but hosting, development and upkeep add up. Total cost of ownership over several years depends on how well the platform fits your business, not on the license alone.

What is the best open source ecommerce platform?

For mid-market and enterprise stores, especially B2B, Magento Open Source and Adobe Commerce are the most established choices, with the largest developer and extension ecosystems. Smaller frameworks such as Spree Commerce and Sylius are used for more specialist builds.

Can a SaaS ecommerce platform handle B2B?

Often, yes. Shopify Plus and BigCommerce support company accounts, price lists, net terms and purchase orders. Very large or complex B2B operations, with hundreds of account-specific catalogs or custom ERP pricing, tend to be a better fit for Adobe Commerce.

How do I choose the right ecommerce platform for my business?

Start with how you sell, what your checkout and integrations need, and who will run the platform. Our SaaS vs open source ecommerce quiz walks through those questions in about four minutes, or you can book a 30-minute assessment to talk it through with our team.