For genuinely cold outreach to a well-targeted list, low single digits is reality: around 1–3% replies is workable, 5%+ is excellent. Anyone promising double digits at scale is describing warm audiences or fiction.
Judge on replies, not opens — privacy features (notably Apple Mail) inflate open rates with phantom opens, while a reply is unfakeable human attention. Positive-reply rate is the refined version worth tracking once volume allows.
Reply rate is mostly a list-quality metric wearing a copy costume: the same email to a sharper list doubles its rate. When replies disappoint, fix targeting before rewriting the pitch for the fifth time.