Ecommerce is buying and selling goods or services over the internet. That covers a shopper ordering shoes from a brand's website, a business buying packaging in bulk through an online portal, and a student reselling textbooks on a marketplace. It does not matter whether the payment happens online, only that the order or the terms of the sale are agreed through an online channel. This guide explains what ecommerce is in plain terms, the main types and business models, how big it really is in 2026 using US Census data, how a single order flows through a store, and how to decide which model suits you.

What is ecommerce?

The word is short for electronic commerce. The US Census Bureau, which measures it, defines ecommerce sales as sales of goods and services where the buyer places an order, or the price and terms of the sale are negotiated, over an internet, mobile device, extranet, electronic data interchange, email or other online system. It adds that payment may or may not be made online. So a customer who orders on your website and pays cash on delivery still counts.

A few terms get mixed up with it:

• Ecommerce is the selling itself: the order, the checkout, the fulfilment.
• M-commerce is ecommerce done on a phone or tablet. Same thing, different screen.
• E-business is wider. It includes everything a company does online, such as internal tools, supplier systems and marketing, not only sales.

An ecommerce business, then, is any business whose sales happen mainly through online orders. It might run its own store, sell through marketplaces like eBay and Amazon, or use both. Amazon and eBay both started in 1995, and the core idea has not changed since. What changed is the tooling: today you can open a store in an afternoon, and the harder parts are finding a product people want and keeping the unit economics healthy.

How big is ecommerce in 2026?

The latest quarterly figures from the US Census Bureau put US retail ecommerce sales at an estimated $340.2 billion for the second quarter of 2026, seasonally adjusted. That is up 3.8% from the first quarter and up 12.2% from the second quarter of 2025. Total US retail sales grew 6.7% over the same year, so ecommerce is growing at nearly twice the pace of retail overall. Ecommerce accounted for 17.1% of total retail sales in the quarter.

Read that last number carefully. 17.1% means that more than four out of five retail dollars are still spent in physical shops. Ecommerce is large, but it is not the whole market, and many shoppers mix both. The chart below, from the St. Louis Fed's FRED database using the same Census data, shows the share climbing steadily for two decades, with a sharp jump in 2020 and a slower climb since.

You can check the numbers yourself on the Census Quarterly Retail E-Commerce Sales page and the FRED series E-Commerce Retail Sales as a Percent of Total Sales. Both update each quarter, and the Census page notes that revised estimates follow in later releases. These figures cover US retail only, so treat them as a guide to direction, not a global total.

Types of ecommerce

People usually split ecommerce by who sells to whom:

For someone starting a small online business, B2C and D2C are the relevant ones, with C2C as a way to test products on a marketplace first. B2B is a different game, with larger orders, longer sales cycles and account-based pricing.

Ecommerce business models

The type tells you who the customer is. The business model tells you how you get the product to them, and it decides your costs and risk. These are the models most new sellers pick between:

There is no best model, only the best fit for your cash, time and risk tolerance. Dropshipping and print on demand let you test an idea without buying stock. Own stock and private label give you control and better margins once demand is proven. Many sellers start with the first and move toward the second. Our comparison of dropshipping vs ecommerce goes into that choice, and what dropshipping is and how it works explains the first model in detail.

Where ecommerce happens: store, marketplace or both

You can sell from your own store, on a marketplace, or on both. A store gives you the brand, the customer data and full control of the checkout, but you must bring your own traffic. A marketplace such as eBay or Amazon brings built-in shoppers, but you play by its rules, pay its fees and compete on its page. Our guide to the best ecommerce platforms compares store builders, and the eBay Seller Hub guide shows what running a marketplace shop involves day to day.

How an ecommerce order works, step by step

1. A shopper finds your product through search, social media, an ad, an email or a marketplace listing.
2. They view the product page and decide, based on photos, price, reviews and delivery information.
3. They check out. The store collects the address, shipping choice and payment.
4. A payment processor takes the payment and deducts its fee before paying you.
5. The order is fulfilled. You pack it, a warehouse ships it, or a supplier ships it directly.
6. The carrier delivers and the customer gets tracking along the way.
7. After-sales: support questions, returns, refunds and review requests.

Each step has a cost and a way to fail, which is why running the numbers per order matters more than watching revenue. For the fulfilment side in depth, see our guide to dropshipping order fulfillment.

A worked example: the economics of one order

Take a pet grooming glove that sells for $39 in a small online store. These numbers are illustrations, so replace them with your own.

That is about 27% of the selling price. Two lessons sit in this table. First, revenue is a vanity number: $39 turns into $10.57. Second, advertising is the line most likely to wreck the maths. If ad cost per sale rises from $10 to $20, the profit falls to $0.57. Most new stores fail not because the product is bad, but because the cost of getting a customer is higher than the margin. Before you build anything, estimate your margin per order and what you can afford to spend on a customer.

Ecommerce vs traditional retail

The products are often the same. The difference is where the costs sit and what you can see. A physical shop pays rent, staff and stock up front and sees only the customers who walk in. An online store swaps the rent for a platform subscription and advertising, and sees every visitor, every abandoned cart and every search term.

Neither is better in the abstract. The Census figure above is the clearest reminder: most spending still happens in shops, so ecommerce is an extra channel for many businesses and the only channel for others.

Ecommerce terms you will hear

New sellers meet a lot of jargon. These are the terms worth knowing before you read any ecommerce advice:

Of these, CAC and landed cost matter most for a new store. If CAC is higher than your profit per order before ads, the store loses money on every sale however good the product looks.

Advantages and drawbacks of ecommerce

How to start an ecommerce business

1. Choose a narrow niche and a customer. "Dog owners with small apartments" beats "pet products". Browse best dropshipping niches for ideas.
2. Pick a model. Use the table above and be honest about how much cash you can risk.
3. Source your product. Order samples from every supplier before you sell anything.
4. Choose where to sell. A store builder, a marketplace, or both.
5. Set up payments, shipping and policies. Write clear delivery times and a returns page.
6. Run the unit economics as in the example above, and drop any product that does not leave room after ads.
7. Test with a small ad budget, keep what sells, and cut what does not.

If you want a step-by-step version, our guide on how to start an ecommerce business goes further.

Where Spocket fits

Spocket is a supplier marketplace for dropshipping. It gives an ecommerce store access to suppliers, many based in the US and EU, whose products you can import into your store without buying stock. It connects to Shopify, WooCommerce, Wix, BigCommerce, Squarespace, eBay and other platforms, and orders can be fulfilled automatically with your branded invoice. Its US and EU suppliers advertise shipping in 2 to 7 days, which you should confirm with a test order. Plans start at $39.99 a month with a 7-day trial. Browse trending products to see what is on offer and the Shopify integration to see how it connects, or start the trial here.

Common ecommerce mistakes

• Judging success by revenue. Track profit per order after all costs.
• Selling a broad range. A focused store is easier to market and to trust.
• Promising delivery times you cannot meet. Late parcels drive refunds and bad reviews.
• Skipping samples. You cannot judge quality from a supplier photo.
• Ignoring policies. Shipping, returns and privacy pages build trust and protect you.
• Spending on ads before testing the product. Validate demand cheaply first.

The short version

A sensible first project is small and measurable. Pick one product, sell it for a few weeks through one channel, and write down four numbers: orders, revenue, profit per order after every cost, and how much you spent on ads. Those four numbers tell you whether to carry on, change the price, change the product or stop. Most of the skill in ecommerce is reading them honestly and acting on them quickly, long before you worry about logos, apps or fancy store themes.

Ecommerce is selling over the internet, and in the US it now accounts for just over 17% of retail sales and is growing faster than retail as a whole. Pick a type and a model that match your budget, work out the profit on a single order before you build, and test small. When you are ready to try the dropshipping route, start your Spocket trial.