Cost per channel: the full picture
Most channel comparisons pick a single metric and declare a winner. Cost per contact favors email. Engagement rate favors calls. Neither tells the complete story. The number that actually matters is cost per qualified conversation — the point at which a human decides whether to move forward.
| Channel | Cost per contact | Response/connect rate | Cost per conversation | Setup time |
|---|---|---|---|---|
| Cold email (Distribute) | $0.07 | 4-8% | $1-2 | 5 min |
| Cold email (DIY) | $0.20-0.50 | 2-4% | $5-25 | 2-3 weeks |
| LinkedIn InMail | $3-5 | 10-20% | $20-50 | 1 day |
| Cold calling | $15-30 | 3-8% connect | $100-300 | SDR hire |
| LinkedIn ads | $8-15 per click | 0.5-2% CTR | $60-150 | 1-2 weeks |
Key point
Cold email wins on cost per conversation by 10-100x depending on the comparison. The only scenario where other channels close the gap is niche high-ACV deals where response quality matters more than cost.Cold email: best for volume with targeting
Cold email works best when you have a specific ICP and a clear problem to reference. The economics are hard to match: $0.07 per contact means you can reach 350 people for $25 and expect 14 replies. Two converting at $500 MRR each is 45x ROI on that campaign.
What cold email doesn't do well: very senior executives who get hundreds of unsolicited emails daily, niche lists where everyone knows everyone (word gets around), or audiences where email deliverability is poor due to domain-heavy industries filtering aggressively.
LinkedIn InMail: best for senior contacts with no email
InMail's main use case is people who don't have a discoverable work email. Some C-suite contacts, board members, and highly sought-after profiles fall into this category. At $3-5 per message, InMail is only worth it when the deal value justifies the cost premium.
InMail also works as a follow-up channel after a cold email sequence. Someone who didn't reply to email but sees an InMail from the same company three days later gets a second-channel signal. This multichannel approach improves overall response rates by 10-20% for accounts that warrant the extra spend.
Cold calling: best for enterprise, worst for volume
Cold calling has the highest cost per contact of any outbound channel — you're paying for an SDR's time plus data plus dialers. At $15-30 per conversation attempt with a 5-8% connect rate, you're looking at $200-600 per actual conversation. That number only makes sense for deals above $50,000 ACV.
What cold calling does better than email: real-time objection handling, immediate qualification, and tone of voice cues. A skilled SDR can move a prospect further in a 5-minute call than three email exchanges. The problem is you can't do 200 calls a day and expect quality conversations.
Pro tip
The best use of cold calling is as a second touch after email. Use cold email to generate initial responses, then call the prospects who opened multiple times or replied but went cold. Calling someone who's already seen your message converts at 3-5x the rate of a truly cold call.How to sequence channels by deal size
| Deal size | Primary channel | Secondary channel | Avoid |
|---|---|---|---|
| Under $5k ACV | Cold email | LinkedIn ads (retarget) | Cold calling, InMail |
| $5k-15k ACV | Cold email | LinkedIn ads + InMail (senior contacts) | Cold calling for volume |
| $15k-50k ACV | Cold email + LinkedIn ads | Cold calling (warm leads only) | Cold calling cold list |
| Over $50k ACV | All channels (ABM) | SDR cold calling | Nothing, run all |
The sequencing matters as much as the channel selection. Start with the lowest-cost channel to validate the ICP and messaging. If cold email produces replies, the ICP is right and the message works. Then layer in higher-cost channels for accounts that don't respond to email.
Which channel to start with
For any company under $1M ARR: start with cold email. The $25 experiment reaches 350 people and tells you within a week whether your ICP description is right, whether your message lands, and whether the channel works for your market. No other channel gives you that feedback loop at that cost.
LinkedIn ads, cold calling, and InMail all require more investment before you get signal. An ad campaign needs 2 weeks and $1,500 minimum to learn. Cold calling requires an SDR. InMail credits run out fast. Cold email scales from $25 tests to $2,500 campaigns with the same workflow.