Every year, ecommerce brands lose $18 billion in annual revenue due to abandoned carts at checkout. Many marketplace founders underestimate how much checkout friction can hurt conversions. 

A single shopping cart works fine when you’re selling products from one vendor. But for a multi-vendor marketplace, buyers want to purchase from multiple sellers in a single checkout. 

A multi-vendor shopping cart allows buyers to add products from different sellers and check out in a single transaction. It’s one of the simplest ways to improve the buying experience, but a lot of marketplace platforms don’t offer this natively.

In this article, we’ll discuss how you can build a multi-vendor shopping cart and grow your online marketplace.

Single vendor shopping cart vs multi-vendor shopping cart

A single vendor shopping cart allows customers to purchase from only one seller at a time. A multi-vendor shopping cart lets buyers check out items from multiple sellers in the same cart.

The key difference lies in how your marketplace processes checkout, payments, and order fulfillment across different vendors.

Smaller multi-vendor marketplaces often start with a single-vendor cart because it’s easier to build and maintain. It avoids complex logic like commission splits and vendor-specific shipping.

But as you onboard more sellers, the single-vendor checkout creates friction. Buyers have to repeat the checkout process for each seller, which increases drop-offs and hurts conversion rates.

With a multi-vendor checkout, buyers can browse freely across your entire marketplace, add what they need, and complete their purchase in one smooth flow. This leads to higher purchase rates and average order values.

Here’s a quick overview of the key differences between single vendor and multi-vendor shopping carts:

Single vendor shopping cart

• One seller per checkout
• One shipping option per order
• Single order goes to a single seller
• Only one payout is done at a time
• If customers are purchasing from multiple sellers, the customer experience is repetitive

Multivendor shopping cart

• All sellers in one unified checkout
• Option to set up separate shipping options per vendor
• Orders are split and sent to multiple vendors
• Payouts routed to appropriate vendors
• Seamless checkout experience

Why is a multi-vendor shopping cart important for marketplaces?

According to the Baymard Institute, 18% of U.S. shoppers abandon their carts because checkout is too long or complex. When buyers shop across multiple vendors, they expect one unified checkout flow. 

Despite this, some marketplace founders overlook the checkout experience.

Here are a few reasons why a multi-vendor shopping cart is important for your marketplace: 

Lower cart abandonment rate

Customers abandon carts if they see unexpected fees, like multiple shipping fees or duplicate form entries at checkout. A multi-vendor cart shows vendor-specific pricing, taxes, and shipping in real-time. This transparency helps you lower cart abandonment.

Better conversion rate

A cart with multiple steps or unnecessary fields kills conversions. A multi-vendor shopping cart lets buyers complete a single transaction across sellers with fewer clicks and no repeated forms. 

Higher average order value (AOV)

One of the major benefits of a multivendor marketplace is its ability to improve AOV. A study by Forrester, and commissioned by Nautical found that companies that launched a marketplace saw a 36% increase in AOV. This is in large part due to expanded product assortment available with more sellers. But without a multivendor shopping cart, customers face significnatly more friction to checkout all the items in their cart, resulting in lower AOV. 

Time to checkout completion

People have short attention spans.Longer checkout times increase the chance of cart abandonment. A multi-vendor shopping cart combines everything into a single, intuitive flow to reduce distractions. With one cart, one payment, and fewer steps, buyers complete checkout faster. 

High customer retention rate

Retaining a customer is up to 5 to 25 times cheaper than acquiring a new one. A multi-vendor cart helps increase retention by reducing checkout friction when customers buy from multiple sellers. 

Pro Tip: To assess how your shopping cart is impacting the customer experience, you can use a customer experience tracker template to monitor key metrics.

When does a multi-vendor shopping cart make sense?

Not every marketplace needs a multi-vendor shopping cart. If you're early in your marketplace development, it's important to match your checkout experience to your business model.

For example, if you're building a services marketplace, like freelancers, bookings, or appointments, you don’t need it. This is because transactions happen one-to-one between the buyer and a single provider. A single-vendor checkout is enough.

But if you're launching a physical goods marketplace, a multi-vendor cart is essential. Buyers expect to purchase from multiple sellers in a single transaction, like they do on Amazon. 

Here’s when a multi-vendor shopping cart becomes a must-have:

• Buyers want to bundle items from different vendors
• Your vendors manage their own fulfillment
• You monetize through commission or fees
• You want to offer a seamless buyer experience

3 Approaches to building a multi-vendor shopping cart for your marketplace

Before you build a shopping cart, it's important to understand the complexity involved in multi-vendor commerce. 

Managing multiple sellers in a single checkout means your system needs to support vendor-specific shipping rates and methods. You also need to consider tax rules and calculate custom commission structures per order.

Then you have to split and route each order to the correct vendor, process payouts accurately and on time, and manage discounts or promotions that span across multiple sellers. 

Here are three approaches to building a multi-vendor shopping cart into your marketplace:

1. Manually coordinate logistics and payouts

In the earliest stages of a multi-vendor marketplace, some teams try to get by without building cart logic. They take orders via a shared cart, then manually split them between vendors after checkout. 

Payouts are tracked in spreadsheets, and communication with sellers happens over email or chat.

This can work well for a marketplace MVP if you:

• Are testing a new market or seller vertical
• Operate with 3–5 vendors 
• Have a limited budget 

But this manual setup breaks down quickly as your marketplace grows. Sellers need more control and visibility into their orders. You’ll also struggle with applying different commission rates or tax rules for each vendor.

Buyers also expect faster fulfillment and real-time updates, which are difficult to deliver without automation. 

If you’re still figuring out your marketplace, Nautical’s Marketplace Bootcamp covers everything from buyer experience to backend setup.

2. Building a custom multi-vendor checkout layer

Some founders try to create a marketplace by layering apps, plugins, or custom code onto single-seller platforms like Shopify or WooCommerce. These tools mimic multi-vendor features but aren't native to the platform.

To make it work, you’ll need to:

• Write custom code logic to track which items belong to which vendor
• Split orders manually at checkout and send each part to the right seller
• Manage different tax, shipping, and commission rules across vendors
• Integrate with a payment system that supports split payouts

But as more vendors join and order volume increases, these setups cause problems. Shipping rules conflict, payouts become hard to track, and every new vendor needs custom, technical fixes. 

3. Using a platform that supports multi-vendor checkout by default

Instead of assembling your marketplace from pieced-together systems, you can use marketplace software that natively supports a multi-vendor shopping cart.

This allows you to automate:

• Order splitting and routing to sellers
• Vendor-specific shipping and tax rules during checkout
• Calculating commissions per seller
• Sending payouts directly to sellers

With marketplace platforms like Nautical Commerce, you don’t need to hire a developer team to recreate features that already exist. You also don’t have to worry about breaking the system when you onboard multiple vendors.

How Nautical Commerce supports a multi-vendor shopping cart

Nautical Commerce is purpose-built for merchants who run marketplaces and need multi-vendor shopping carts. With Nautical, you can build and launch quickly without requiring a development team.

Nautical’s no-code marketplace software includes a drag-and-drop storefront builder you can use without technical experience. Or you can take advantage of the headless commerce capabilities to create a fully customized marketplace. The platform connects with thousands of third-party apps through direct integrations, Zapier, and an open API.

Nautical’s native multi-vendor shopping cart automatically splits orders and applies vendor-specific shipping methods. Nautical also helps you manage payments and fulfillment through seller-level suborders without needing coding knowledge. 

Here’s how Nautical’s multi-vendor shopping cart works:

Seamless product discovery across multiple sellers

With storefronts built on Nautical, buyers can easily browse and search products from multiple vendors on one unified website. 

Features like advanced product filtering, sorting, featured collections, and related products make it easy to navigate a broad catalog from different sellers. 

Buyers can also switch currencies in multi-currency environments and save favorites using the wishlist feature.

Multi-vendor shopping cart

Once buyers add items from different vendors into their cart, Nautical handles the complexity behind the scenes. 

Buyers can adjust quantities, remove items, or save for later, all within a single cart view. 

Before checking out, buyers can enter notes on their order, which are passed to vendors for fulfillment context. Minimum order requirements can also be enforced if needed.

Unified checkout flow for multi-vendor transactions

During checkout, Nautical intelligently splits the order by seller while keeping the process seamless for the buyer. 

Each vendor’s shipping options are calculated individually, allowing buyers to choose different methods and rates per seller. 

Buyers can complete the purchase or submit a quote, attach PO numbers, and apply discount codes. Nautical supports both authenticated and guest checkouts, with optional login requirements based on your settings.

They can also choose from multiple payment methods that you choose to offer such as Credit/Debit Card, Stripe, PayPal, or Trolley. This gives your buyers more options to choose from and checkout in one single transaction.

Post-purchase transparency

After checkout, Nautical generates one marketplace order with separate suborders routed to the respective vendors. 

Buyers can log in to view order and quote history, track fulfillment progress, and manage saved addresses for future purchases. 

The storefront is fully responsive, ensuring a smooth experience across mobile, tablet, and desktop.

Multi-vendor order routing and payouts

In the backend, Nautical routes each order directly to specific sellers with full item details, buyer notes, shipping selection, and fulfillment instructions. 

Nautical also calculates each seller’s payout after deducting platform fees and commissions. The system supports milestone-based disbursements, partial refunds, and custom payout schedules. 

Payouts to sellers can be sent automatically via integrated gateways like Stripe Connect, PayPal, and Trolley. 

Future-proof your multi-vendor marketplace

If your marketplace has third-party sellers offering products that buyers want to combine in a single order, you need a multi-vendor shopping cart. 

It’s possible to start by managing logistics manually or building custom checkout logic on a single-vendor platform. But as your vendors and orders increase, you need automation to simplify the process.

Nautical Commerce offers an all-in-one platform for building a multi-vendor marketplace with a multi-vendor shopping cart. It automates order splitting, shipping calculations, commission tracking, and vendor payouts. This helps you deliver a seamless buyer experience with high customer retention.

You can test it out yourself by starting a free trial today.

If you’re looking for more details about our multi-vendor shopping cart or other product features, check out our in-depth product guide here.