E-commerce website cost: everything that goes into the number

1. What drives e-commerce cost

E-commerce cost scales with complexity, not page count. A store selling three product sizes in one color requires a fundamentally different build from one with 500 SKUs, eight size options, twelve colors, bundle pricing, backorder management, and a POS that syncs with physical retail. Both are "online stores," but they're not comparable in build time or cost.

The five levers that determine what an online store costs:

• Catalog structure. Three-color shirts are simple; per-combination prices, SKUs and stock cost more. Product/variant counts, nested options, bundles and mixed digital/physical goods determine complexity.
• Shipping and tax logic: Flat-rate shipping is trivial. Carrier-calculated rates (USPS, UPS, FedEx, with real-time weight and zone lookup) require an integration layer. Multi-warehouse fulfillment, free shipping thresholds, and per-product shipping classes add more. Tax handling gets complicated fast if you collect sales tax across multiple states and need to feed a tax calculation service like TaxJar or Avalara.
• Customer account features. Guest checkout only is cheap. Add customer accounts with order history and a logged-in experience. Then add saved addresses, wishlists, loyalty points, and a B2B pricing tier for wholesale customers. Each is a development layer. The ones you need depend entirely on your business model.
• Payment and subscription complexity. A one-time charge through Stripe is standard. Add subscription billing (weekly, monthly, quarterly boxes), installment plans (buy now, pay later), split payments, or ACH and the payment logic becomes a significant project on its own.
• Integrations. Inventory systems, accounting platforms (QuickBooks, Xero), email marketing (Klaviyo, Mailchimp), a CRM, a print-on-demand fulfillment service, a shipping label printer — every integration requires API work, data mapping, and ongoing maintenance when those third-party APIs change.

This is why a legitimate developer scopes before quoting for e-commerce. A fixed price list for "an online store" is either priced sky-high to cover any possibility, or low enough to suggest a surface-level build. Scope first, then quote.

2. The platform fee nobody talks about upfront

If you're comparing a custom-built store to a hosted platform, the headline price difference exists, but it's not the whole story. Hosted platforms lead with their monthly plan. That's not the total cost.

Shopify's pricing (as of mid-2026) runs from $39/month (Basic) to $399/month (Advanced), billed annually. WooCommerce is technically free to install, but requires WordPress hosting (inadequate on shared servers at any meaningful traffic level), WooCommerce-compatible themes, and paid extensions for features the base plugin doesn't include. Squarespace Commerce runs $36–$65/month (as of mid-2026) depending on plan.

Here's what those numbers don't include:

• Transaction fees on top of your payment processor: Shopify charges 0.5%–2% per transaction¹ (less on higher plans) unless you use Shopify Payments. Your payment processor charges separately on top of that. More in the next section.
• App costs for missing features: The base Shopify plan doesn't include subscription billing, advanced reporting, product bundles, back-in-stock notifications, or customizable checkout flows. Those are paid apps, each running $10–$50/month. See section 4 for details.
• Premium themes: Shopify's free themes are functional but generic. A quality premium theme runs $150–$400 upfront and commonly needs developer customization if you want it to match your brand.
• Custom development for anything outside the template: Any modification to a Shopify theme's checkout flow, any feature not available as an app, any integration with a non-standard service. This is paid development work that doesn't give you anything you own. The modifications live on top of a platform you're renting.

The platform fee is the combined cost of the plan, transaction cuts, app stack, and paid development for any customizations beyond the template—not the $39 or $79/month headline price. Add those up before comparing to a custom build. See the full Shopify vs. custom comparison →

3. Transaction fees: the cost that scales with your revenue

This is the cost that's easiest to underestimate when starting and hardest to ignore as you scale. Transaction fees compound with every sale, every month, every year. A percentage of revenue is a permanent overhead tax on your business.

Here's how the math works across different store setups:

At $10,000/month in sales, the difference between a custom store with Stripe and Shopify Basic with a third-party processor is about $2,400/year in transaction fees alone²¹. At $50,000/month, it's $12,000/year. That money leaves your account every year regardless of whether you've gained new features or value from the platform.

A few important nuances: if you use Shopify Payments as your processor, Shopify waives its own transaction fee. Shopify Payments is Stripe-based and competitively priced. The tradeoff is that your payment processing locks into Shopify. If you leave the platform, you need to migrate payment processing too. It's not a trap, but it's a coupling worth understanding.

On a custom store, you choose your payment processor and can switch freely. If Stripe raises rates or a better option appears, the change is a configuration update, not a platform migration.

4. App stack creep: the subscription you didn't plan for

Hosted platform pricing is structured to show you a low base rate and let you discover the rest after you're committed. The app marketplace is the mechanism. Most of the features an operating store needs are either omitted from the base plan or included in a limited version that requires an upgrade.

Here's what Shopify stores commonly pay in apps on top of the base plan:

A store using a handful of these (subscriptions, reviews, email, and custom shipping) commonly runs $50–$300/month in apps, with a full feature set landing around $150–$300/month. A store with a more complex feature set can push $400–$600/month before it looks like anything special from the outside.

Compare cumulative app costs, not base subscriptions, with custom builds. Individually useful integrations add up; owned, built-in features change value over 24 or 36 months.

There's also a technical cost to the app stack not reflected in subscription fees: app conflicts, checkout slowdowns from multiple third-party scripts, inconsistent UI/UX across apps that weren't designed together, and the operational overhead of managing a dozen separate subscriptions and vendor relationships. Operating stores deal with this constantly.

5. Five-year cost: custom vs. Shopify vs. WooCommerce

Numbers are the only way to make this comparison. Below is a realistic five-year cost comparison for a mid-size store doing modest volume: not a high-growth startup, not a solo seller, but an established small business with a substantial product catalog and feature requirements. Assumptions are listed under the table.

*Transaction fee comparison assumes $10,000/month in sales. With Shopify Payments, the platform fee is waived. With a third-party processor on Shopify Basic, Shopify charges an additional 2% per transaction¹. That's $2,400/year extra at $10k/month, or about $12,000 over five years.

Adding it up: a custom store runs about $9,900–$25,800 over five years (build plus hosting). Shopify Basic with a full app stack runs about $11,500–$20,700 on Shopify Payments, or $23,500–$32,700 with a third-party processor at $10k/month. Smaller custom builds come out ahead; a larger build against a lighter app stack may not.

The comparison changes significantly based on:

• Your sales volume: Low volume and a basic feature set keep Shopify's base cost manageable. Higher volume makes transaction fees compound significantly.
• Your feature needs: A store running on Shopify Basic with no paid apps is economical. A store needing five apps to function is a different math problem.
• How long you're running it: The platform's amortization advantage erodes over time. A custom build that costs more upfront becomes fully paid for. A platform subscription is permanent.

The right answer isn't "custom always wins." It's "run the numbers for your volume and feature set over a realistic timeline, then decide." This guide exists because most e-commerce cost comparisons stop at the headline plan price. Full Shopify vs. custom breakdown →

6. What a custom e-commerce build includes

Understanding what's in a custom e-commerce quote matters because it's the only way to compare it to a platform on equal footing. Here's what a well-scoped custom store build covers as standard:

• Product catalog with variant management. Products, categories, subcategories, and variants (size, color, material, or whatever your product structure requires). Stock tracking per variant. Product images with alt text. Simple and configurable products. The data model is designed to match your actual inventory, not forced into a platform's schema.
• Shopping cart and session management. Persistent cart across browser sessions, coupon and discount code application, cart abandonment recovery (depending on scope), and clear line-item pricing with tax and shipping estimates before checkout.
• Checkout with integrated payment processing: Not a "checkout" that hands off to PayPal's hosted page and returns a result. Instead, an on-domain checkout keeping the customer in your brand throughout the full payment flow. PCI compliance handled through processor tokenization. Support for cards, Apple Pay, Google Pay, and any other methods the processor supports.
• Shipping rate calculation: At minimum, flat-rate and free shipping. Carrier-calculated rates (USPS, UPS, FedEx) require an API integration and are scoped based on your needs. Multiple shipping methods, expedited options, and international shipping are all possible.
• Order management admin: A backend interface where you or your staff can view orders, update order status, process refunds, print packing slips, and manage the operational side of the store without touching code. Built for the people who will use it daily, not for developers.
• Customer accounts and order history: Optional guest checkout and optional customer account creation. Logged-in customers see their order history and can track shipments. The tradeoff between requiring accounts and guest checkout is discussed and decided during the scope conversation.
• SEO: Product labels give Google images, prices and stock status. Social shares show correct photos/titles. Clean code and sitemaps support complete crawling and higher rankings with rich previews.
• Mobile-first responsive build: The checkout works on phones, product pages work on tablets, buttons are big enough to tap, and images load efficiently on mobile connections. Mobile isn't an afterthought. It's where most e-commerce traffic comes from.

What a custom build doesn't include as a default: content writing, product photography, email marketing templates, or ad account setup. These require separate planning and budget, distinct from the store infrastructure itself.

See ArdinGate's custom e-commerce service →

7. Ongoing costs after launch

A custom-built store has a small, predictable set of ongoing costs. There are no surprises after the first year unless you add new features or integrations.

• Managed hosting: $60–$100/month. Server, automated backups, SSL renewal, security monitoring and breakage support handle promotions, maintain uptime and enable recovery. Cheap shared hosting lacks the stability/security payment and customer data require. Full hosting cost breakdown →
• Domain renewal: $15–$50/year. Annual. Your domain registrar bills you once a year. Auto-renew is on. That's it.
• Payment processor fees: 2.9% + $0.30 per transaction. Stripe's standard rate. Square and PayPal charge similarly. Volume discounts exist at high enough transaction levels and are worth negotiating once you reach them.
• Third-party services you choose to use. Email marketing platform, SMS notification service, fulfillment partner, tax calculation service if you sell in many states. These are optional and chosen by you, not mandatory platform components.

Future development (new product types, new shipping integrations, loyalty programs, wholesale pricing tiers) is scoped and priced per project when you need it. It's never bundled into a monthly fee you pay regardless of whether you're building anything new.

8. When a platform is the right call

This guide makes a strong case for custom-built stores, but that case has limits. Legitimate situations exist where a hosted platform is the better choice.

Product validation. Shopify suits testing product-market fit within a week. Platform fees fund the experiment: rebuild if successful; otherwise avoid losing a substantial build investment.

You're deeply embedded in Shopify's fulfillment ecosystem. Shopify Fulfillment Network, Shopify Shipping rates, and deep integrations with Shopify's logistics partners are advantages for certain types of businesses. If you rely on those, leaving the platform means rebuilding your fulfillment workflow, which is its own cost. For stores in that position, staying makes sense.

You need a very short timeline and a large app marketplace. The Shopify app marketplace covers a broad range of edge cases. If you need a specific integration that has a mature Shopify app, using it on Shopify may be faster and cheaper than building custom. That's a legitimate advantage for niche requirements with good app coverage.

You have no budget for a custom build. Custom e-commerce requires meaningful upfront investment. If bootstrapping rules that out, starting on a platform beats not starting. Usually, the goal is enough volume to make a custom migration economically worthwhile.

Platforms are tools, not inherently inferior. The problem is adopting them by default without running the math on whether they're cheaper for your situation over your planned timeline. Most businesses skip that comparison entirely. This guide exists to simplify it.

9. Key takeaways

• E-commerce cost scales with catalog complexity, shipping logic, customer account features, payment configuration, and integrations, not page count. Any quote without a defined scope is a guess.
• Hosted platform pricing has four components: the monthly plan, transaction fees on top of the payment processor, a paid app stack for features the base plan omits, and paid development for any customization outside the template.
• At meaningful sales volume, Shopify's transaction fee on third-party processors (0.5%–2% per sale) compounds into thousands of dollars per year that has no equivalent on a custom store.
• A typical Shopify store commonly runs $50–$300/month in apps, $150–$300 for a full feature set. Over five years, a full feature set runs $9,000–$18,000 for capabilities that would be built into a custom store's code.
• On a custom store, ongoing costs are hosting ($60–$100/month), domain renewal ($15–$50/year), and payment processor rates. No platform fee, no app subscriptions, no per-feature rentals.
• Platforms are the right call when you're validating a product, when you're deeply embedded in a platform's fulfillment ecosystem, or when your budget doesn't support a custom build upfront.
• The break-even point between a custom build (from $6,300) and a hosted platform is usually somewhere between about 13 months and 4 years for a smaller store build, depending on your sales volume and app stack; larger builds take longer. Run the math for your numbers, not a generic estimate.

10. Common questions

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