The pipeline maths: work backwards from a meeting

Before you send a single email, do the arithmetic — because it tells you whether the channel can even work for your deal size and whether you are building toward the right volume targets. The whole pipeline is a chain of conversion rates, and you size it from the meeting backwards.

The 2025 benchmarks to anchor on (Lemlist / Mailmeteor aggregate data, 2025):

• Reply rate: ~5% is a solid baseline; the cross-industry average sits closer to 3.4%. SaaS often sits under 2% on a cold list, so know your floor before you build a plan.
• Meeting-booked rate: 0.8–1.5% of emails sent is good; top-quartile teams hit 1.5–3%. On a flat cold list with generic copy, expect 0.3–0.6%. On signal-triggered sends with relevant personalisation, 1.2–3.2%.
• Cost-per-lead by channel: Cold email typically runs £30–£80 per qualified lead when you factor in tooling and time. LinkedIn paid runs £50–£150. Paid search (B2B SaaS) runs £80–£200. SEO-generated leads cost nearly nothing per lead once the content is ranking, which is why organic search is the long-term play that changes the unit economics of the whole machine.
• Rule of thumb: roughly 300 cold emails generate one qualified meeting at average conversion rates (Lemlist, 2025).

So to book ten qualified meetings a month off a cold list, you are looking at roughly 3,000 sends per month. At safe per-domain daily volumes (50 sends maximum per domain), that means at least two to three warmed domains running in parallel. Switch to signal-triggered sends and the same ten meetings might take a third of the volume — 1,000 sends — which is the entire argument for spending your effort on signal quality rather than raw scale.

This is also the cheapest place to discover the channel does not fit. If your average contract value cannot absorb £300–£800 in tooling and time per meeting booked, cold email is the wrong primary channel and you should be in The lead gen channels worth your time recalculating which motion fits your deal size and sales cycle.

Run your own numbers before committing budget. The funnel metrics that connect pipeline to revenue are in engagement rate, click rate, and impressions; the cost-side connects to CAC and LTV.