B2B ecommerce for distributors: what it changes

Online ordering is no longer something only the largest distributors do. Contractors order from their phones at night, reorder from saved lists and check stock before they drive to the counter. For a supply house deciding whether to build or expand online ordering, the question isn't only whether customers will use it. It's what changes about how you know your customers once they do.

This guide covers where large distributors are today, what online ordering changes for an independent, and how to keep track of accounts that stop talking to your counter.

Where the big distributors are

The largest players have moved a meaningful share of their business online.

• Watsco, the largest HVAC distributor in the US, did $2.75 billion in e-commerce sales over the 12 months through September, or 37% of revenue. E-commerce grew 10% in the third quarter while total sales grew 7% (Watsco Q3 2026 release).
• On its October call, Watsco said its larger, tech-enabled contractors buy more than 50% through e-commerce (transcript).
• Rexel's North American digital sales reached 27% of sales in the first half of 2026 (inside.lighting).
• Watsco has invested more than $250 million in digital tools over five years (Digital Commerce 360).

Adoption isn't even across customers, though. Describing the plumbing contractors served by The Granite Group, which it just acquired, Watsco said those customers are "slightly less technology-enabled today" than its HVAC contractors.

What online ordering changes for a supply house

It makes buying easier

Contractors can order outside counter hours, repeat past orders and see what's in stock. For routine items, that saves both sides time.

It removes a conversation

When a contractor walks up to the counter, your staff hears things: a big job starting, a slow month, a competitor offering a better price. When the same contractor orders online, none of that reaches you. The order shows up, or it doesn't.

It makes customers easier to lose without noticing

A customer who orders online and then stops simply stops. There's no last awkward phone call and no change in tone at the counter. If nobody is watching each account's ordering pattern, the first sign is often a sales report months later.

It changes what reps do

If routine reorders move online, reps have more time for the conversations that matter: new jobs, pricing questions and accounts that have slowed down. That only works if reps know which accounts need them.

How to plan for it

1. Find out who wants it. Ask your top 50 accounts how they'd like to order. Larger contractors with office staff are more likely to want online ordering than a two-person shop.
2. Start with reorders. Saved lists and order history cover most of what repeat customers need.
3. Track each customer across channels. Make sure online, phone, counter and rep orders all land under the same account, so you see one ordering pattern, not four partial ones.
4. Watch each account's rhythm. Know how often each customer normally orders, regardless of channel, and flag the ones that go past it.
5. Give reps a weekly list. Customers who slipped from their normal pattern, sorted by value, with anything in your records that might explain it.
6. Review after 90 days. Check which customers moved online, whether their spend went up or down, and whether any of them went quiet.

Common mistakes

• Measuring only online sales growth. A customer who moves from the counter to online is the same customer. The number that matters is whether total spend per account grows.
• Treating online customers as low touch. Easy ordering isn't the same as loyalty. Contractors often buy from more than one supplier.
• Splitting the data. If online orders sit in a separate system, nobody sees the full picture for an account.

Frequently asked questions

Should a small distributor offer online ordering? It depends on your customers. Ask your largest accounts how they want to order before you build anything. Many independents start with simple reorders from order history for their most active customers.

What percentage of distributor sales are online? It varies a lot by company. Watsco reported 37% of revenue through e-commerce over the last 12 months, and Rexel reported 27% digital sales in North America in the first half of 2026. Smaller distributors are often much lower.

How do I keep relationships strong when customers order online? Watch each account's ordering pattern so you notice when it changes, and use the time reps save on routine orders to call the accounts that slowed down.