Warm outreach is when you reach out to a buyer directly, but with a reason they recognize: a mutual connection, a shared community, or a relevant signal. You are still the one making contact, but the message lands as relevant rather than cold.
In warm outreach you knock on the door yourself, just with context that earns a response. In a warm introduction, someone else opens the door for you. Outreach carries relevance; an intro carries borrowed trust, which is why an intro is the stronger play when one is available.
Warm outreach is the middle of the warm outbound spectrum: warmer than a cold message, cooler than a full intro. For the full range from cold to gold standard, see the warm outbound spectrum.
Via gives your warm outreach the context that makes it land. Before you reach out, you can see who connects you to the buyer and what the relationship is based on, so the message is grounded in something real.