The terms get used interchangeably in vendor material, which is convenient for vendors. The distinction is real and it costs money.
Multichannel
You offer phone, email, chat, and social. Each runs on its own tooling, often with its own team and its own standards. A customer moving between them starts again each time.
Omnichannel
The same channels, but context travels. A customer who raised an issue on chat and then calls does not repeat themselves, and the agent can see what was already said and promised.
The test is simple: can the person answering the phone see the chat the customer had yesterday?
Why it matters more than it sounds
Repeating yourself is one of the most reliably infuriating experiences in customer service, and it is entirely self-inflicted. It also wastes real handle time on every transferred or repeated contact.
Consistency is the second benefit. Separate channel teams drift into different answers to the same question, and customers who get different answers stop trusting all of them.
When multichannel is enough
If customers rarely switch channels mid-issue, and each channel handles distinct contact types, the integration cost may not pay back. Measure how often customers actually cross channels before assuming they do.
Doing it properly
One team, one documented standard, and one view of the customer matters more than any specific platform. Our omnichannel contact center page covers how that is structured.