If your small business website already gets visitors, you don’t need to rebuild it from scratch to start selling online. Several tools let you bolt a shopping cart, product catalog, and checkout onto the site you already have — whether it’s built on WordPress, Squarespace, Wix, or plain HTML.
Table of Contents
And if you’re past the point of just selling your own products — you want other brands or local sellers listing on your site too — that’s a different, slightly bigger project: turning your existing store into a lightweight marketplace. Both paths are covered below, along with the setup steps and mistakes that trip up most small business owners the first time around.
Quick Answer
The fastest way to add an online store to an existing site is to embed a hosted commerce widget — like a Shopify Buy Button, Ecwid store, or Stripe Payment Link — directly into your current pages. If your site runs on WordPress, installing the free WooCommerce plugin is usually the better long-term fit since it turns your existing site into the actual store rather than bolting one on.
If what you actually want is to let other sellers list products on your site, the fix isn’t a new website — it’s a multi-vendor marketplace plugin (Dokan or WC Vendors for WooCommerce, or a marketplace app like Webkul’s Multi Vendor Marketplace for Shopify) layered on top of the store you already have.
Choose the Right Approach for Your Platform
Your current website platform mostly decides your best path. If you’re on WordPress, install the WooCommerce plugin (free) through Plugins > Add New in your dashboard, run its setup wizard, add payment methods, and start adding products — it integrates directly into your existing theme and pages rather than sitting on a separate domain.
If your site is on Squarespace or Wix, you don’t need a third-party tool at all: both platforms have built-in commerce upgrades. Squarespace’s Core plan (around $29/month when billed annually, noticeably more if billed monthly — Squarespace adjusts pricing periodically, so check current rates before budgeting) adds a full store with no transaction fees on top of what you’re already paying for hosting and design.
If your site is custom-built, static, or on a platform without native ecommerce (a basic HTML site, a portfolio builder, etc.), embeddable widgets are your best option. Shopify’s Buy Button — available on Shopify’s entry-level plans — lets you generate a snippet of code and paste it into any existing webpage or blog post to sell individual products with full Shopify checkout behind it. Ecwid by Lightspeed works similarly: its entry-level Starter plan runs around $5/month for up to 10 products, with higher-tier paid plans for larger catalogs and no platform transaction fees on any of them.
For businesses that just need to sell a handful of items or take pre-orders without a full storefront, Stripe Payment Links let you generate a hosted checkout page in minutes with no code — you just paste the link (or embed it as a button) anywhere on your site. There’s no monthly fee, only standard card processing costs. Square Online is a similar no-code option with a free plan, useful if you already use Square for in-person payments and want your online and in-store sales connected.
Setting It Up: The General Steps
Regardless of which tool you choose, the setup flow looks similar. First, create an account with the commerce platform and add your products — names, photos, prices, and descriptions. Second, connect a payment processor (most of these tools have Stripe, PayPal, or their own payments built in) and set up tax and shipping rules for your area.
Third, generate the embed code, widget, or button the platform gives you, and paste it into the pages of your existing site where you want customers to shop — a dedicated “Shop” page is usually cleanest. Test the full purchase flow yourself before announcing the store: add a product to the cart, go through checkout with a real (or test-mode) card, and confirm you receive the order notification and the customer gets a confirmation email. Also check how the embedded store looks on mobile, since a widget styled for a different theme can look out of place on your existing design.
Adding Third-Party Sellers: Turning Your Site Into a Marketplace
Neither WooCommerce nor Shopify is built for multiple vendors by default — both assume one store owner managing one catalog. To let outside sellers list and sell their own products on your existing site, you add a marketplace layer on top of the store you already set up, rather than rebuilding anything.
On WooCommerce, the standard route is a multi-vendor plugin such as Dokan, WC Vendors, WCFM Marketplace, or MultiVendorX. These plugins turn your existing WooCommerce store into a marketplace: each vendor gets their own dashboard to add products, manage their own inventory and orders, and track their own payouts, while you (the site owner) set commission rates, approve new sellers, and approve or moderate listings before they go live.
On Shopify, there’s no equivalent free plugin, but there are two solid options. Shopify Collective is Shopify’s own native feature that lets you add and sell products from other Shopify merchants without holding any inventory yourself — it’s free and built in, but both you and the supplying brand need to be on Shopify, in the same country, using the same currency, so it suits cross-promotion between brands more than open third-party sellers. For a true open marketplace — anyone can apply to sell, you set commissions, and payouts are automated — apps like Webkul’s Multi Vendor Marketplace, Shipturtle, or Nexus add that functionality on top of your existing Shopify store.
If what you actually want is more inventory rather than more sellers — for example, stocking products from wholesale suppliers without warehousing them yourself — dropshipping-style supplier apps (Spocket, Modalyst, and similar) are a lighter-weight option than a full marketplace plugin, since you’re importing supplier catalogs rather than managing independent vendor accounts.
How Vendor Marketplaces Work Day to Day
Once a marketplace plugin or app is installed, the workflow is fairly consistent across tools. You approve or invite vendors, who then create their own seller profile and start listing products — usually subject to your approval before anything goes public. You set a commission structure (a flat percentage per sale is most common, though some plugins support per-vendor or per-category rates), and the plugin automatically splits each order between you and the vendor at checkout.
Payouts to vendors are typically handled on a schedule (weekly or monthly) through PayPal, Stripe Connect, or direct bank transfer, depending on which plugin or app you choose — check this before committing, since payout methods vary a lot between Dokan, WC Vendors, and the Shopify marketplace apps. You’re also responsible for the policies that hold the marketplace together: a seller agreement covering quality standards, returns, and who handles customer service for a given order, since customers will generally see your site’s branding regardless of which vendor fulfilled the purchase.
Tips and Common Mistakes
Don’t skip figuring out shipping and tax settings before launch — these are the most common source of abandoned carts and refund headaches for new small business stores. Set realistic shipping rates or flat rates rather than leaving defaults unconfigured. Match the widget’s fonts and colors to your existing site’s branding; most embeddable tools let you customize this, and an unstyled checkout button looks unfinished and can hurt trust.
Also watch transaction fees closely — entry-level plans often carry higher per-sale processing rates than paid tiers, so if you expect steady sales volume, run the numbers on whether a higher-tier plan saves money over time. Finally, keep your product inventory in one place: if you sell in person too, pick a tool (like Square or Shopify) that syncs online and offline inventory so you don’t oversell.
If you’re adding third-party sellers, the extra mistakes to avoid are moving too fast on vendor approval (vet sellers before giving them a live storefront on your domain), leaving commission rates unclear until after a vendor has already listed products, and underestimating support load — when something goes wrong with a vendor’s order, customers will contact you first, not the vendor, so have a clear escalation process from day one.
Photos
Add an Online Store FAQs
Do I need to rebuild my whole website to add an online store?
No. Tools like WooCommerce (for WordPress), Shopify’s Buy Button, Ecwid, and Stripe Payment Links are designed to be added to an existing site without a rebuild — you install a plugin or paste an embed code into the pages you already have.
What are my options for putting a store on my existing website?
Your main options are a native plugin (WooCommerce on WordPress, built-in commerce on Squarespace or Wix), an embeddable widget (Shopify Buy Button, Ecwid), or a no-code hosted checkout link (Stripe Payment Links, Square Online). Which one fits best depends mostly on what platform your site already runs on.
How do I add third-party sellers to my ecommerce site without rebuilding it?
Install a multi-vendor marketplace plugin or app on top of the store you already have — Dokan, WC Vendors, WCFM, or MultiVendorX for WooCommerce, or a marketplace app like Webkul’s Multi Vendor Marketplace, Shipturtle, or Nexus for Shopify. These add vendor dashboards, commission handling, and payouts without replacing your existing site or catalog.
What’s the cheapest way to start selling online from an existing site?
Stripe Payment Links and Square Online’s free plan have no monthly subscription cost — you only pay standard card processing fees per sale. WooCommerce is also free to install, though you’ll pay for hosting, which you likely already have.
Will adding an online store slow down my existing website?
It can, depending on the tool. Embedded widgets load extra scripts, so test your page speed after installing one. A native plugin like WooCommerce tends to have less front-end overhead than a third-party embed, since it runs as part of your existing site rather than loading an external script.
Can I let other vendors sell on my site without charging them commission?
Yes — most multi-vendor plugins let you set commission to 0% and instead charge a flat listing or membership fee, or run the marketplace simply to offer customers more selection. The commission split is just the default model, not a requirement of the software.
Build It With GTStudios
Need help with your website, app, or small-business tech? GTStudios builds web, apps, and software for small businesses. See how GTStudios can help.
Want dev news in your inbox? Subscribe to the free newsletter.