B2B email prospecting: the complete method, from list to first reply

Writing to strangers to ask for a meeting is a thankless exercise when done badly, and surprisingly rewarding when done well. The difference almost never lies in the genius of an opening line. It lies in a series of ordinary decisions, taken in the right order: who to write to, from which addresses, at what pace, with what message, and what to do when someone replies.

This guide works through that sequence, step by step. It is the method we apply ourselves and that SmartOutbound largely automates. You can follow it with any tool: what matters is the order.

Step 1: decide who you are really writing to

Most failed campaigns fail before the first send. You start with a file of 5,000 contacts "in the target", write a message designed to appeal to everyone, and get polite silence.

Start instead by describing your ideal customer in one precise sentence. Not "SMEs", but for example: "the leaders of recruitment agencies with 5 to 30 employees in the Île-de-France region, who outsource part of their sourcing". That sentence should let you say, looking at a contact record, whether or not the person fits.

Three questions help to narrow it down:

• What concrete problem are these people facing this year, and what is it costing them?
• Who in the company feels that problem day to day and has the power to fix it?
• What distinguishes those who buy quickly from those who "will look at it later"?

A narrow target produces more accurate messages, and more accurate messages produce replies. You can then expand, segment by segment, keeping what works.

Step 2: build a clean list rather than a large one

A prospecting list is judged on two things: whether the people are right and whether the addresses are valid. An invalid address does more than waste a send. It bounces, and email providers look closely at a sender's bounce rate when deciding whether they are reliable.

Before any send, check at least:

• that the address is properly formed and contains no typo;
• that the domain exists and receives email (it has an MX record);
• that it does not belong to a disposable address service;
• that it is not already on your suppression list (people who have unsubscribed or bounced).

These checks are free and instant: SmartOutbound runs them on import, then a second time just before the first email, because a domain can close in between. They do not detect a person who has left a company that is still active. If your file is more than a year old, expect a few bounces of this kind and keep an eye on the rate.

Also be wary of generic addresses such as contact@ or info@. They are not forbidden, but they reply less often and more often end up in a folder that no one reads.

Step 3: set up dedicated sending mailboxes

Sending hundreds of prospecting emails from your main address puts at risk the mailbox that receives your invoices, quotations and client correspondence. The usual practice is to use dedicated mailboxes, often on a domain close to your own. We detail the possible choices in our article on the dedicated prospecting domain.

Every sending domain must be correctly authenticated: SPF, DKIM and DMARC. This is no longer optional. Since February 2024, Gmail and Yahoo have required these records for bulk senders, and Microsoft followed in 2025 for Outlook.com. If those three acronyms mean nothing to you, our step-by-step explanation will let you check yours in a few minutes.

How many mailboxes? Allow plenty. A well-maintained mailbox can send 25 to 40 prospecting emails a day without attracting attention. To contact 3,000 people in a month, with follow-ups, you will therefore need several mailboxes sharing the work.

Step 4: let the mailboxes warm up

A brand-new mailbox that suddenly sends 40 emails to strangers looks exactly like what spam filters are trying to block. "Warmup" means giving it a normal life for a few weeks: exchanges with other mailboxes, replies, messages moved out of the spam folder, and a volume that rises gradually.

Allow two to three weeks before sending at full rate, a little longer if the domain has just been bought. You can start prospecting before then, provided you keep volumes low: five emails a day in the first week, ten in the second. All this is explained in our article on warmup.

Step 5: write a first email people want to read

The first email has one goal: to get a reply. Not to sell, not to explain everything, not to attach a brochure. A reply, even "not now", teaches you something and improves your sender reputation.

Emails that work tend to look alike: short (under 120 words), an opening sentence that shows you know who you are talking to, a problem expressed in the prospect's own words, concrete proof, and a simple request that can be answered in one line. Avoid links and images in this first message: they add nothing at this stage and weigh on deliverability.

We devoted a whole article to writing the first email, with annotated examples. And if you are wondering how to personalise hundreds of messages without spending your evenings on it, read our experience with AI personalisation.

Step 6: plan follow-ups from the start

A large share of replies come after a follow-up. It is not that the prospect changed their mind: they simply had not seen it, had not had time, or had not understood it straight away. A reasonable sequence has three to four emails over two to three weeks, each bringing a new angle, sent in the same thread as the first.

The golden rule: each follow-up must be readable on its own. "I am just getting back in touch" is not a follow-up, it is a reminder. Details, recommended timing and examples are in our guide to follow-ups.

Step 7: configure sending to behave like a human

Prospecting tools let you send in bursts. That is precisely what you should not do. A few simple settings make your sends more natural:

• send during office hours, Monday to Friday, in the prospect's time zone;
• space sends from the same mailbox several minutes apart, with some irregularity;
• spread the volume across your mailboxes rather than pushing one of them;
• automatically stop a campaign whose bounce rate exceeds a few per cent.

For a first campaign, we also recommend approving every first email before it goes out. This is what SmartOutbound calls copilot mode: you review, correct a clumsy opening line, remove a contact who has no place there. After a few dozen approvals, you know whether the campaign is on track.

Step 8: handle replies quickly and well

A positive reply cools quickly. A prospect who writes "yes, call me" on Tuesday morning and hears nothing before Thursday has often already moved on. Gather your replies in one place, sort them, and deal with interested prospects within the hour if you can.

Not all replies are equal. Out-of-office messages, "it's not me, speak to my colleague", rejections and unsubscribe requests each need different handling. We review them in our article on managing replies. At the very least, remember this: an unsubscribe request must be applied immediately, everywhere, and for good.

Step 9: measure what matters

For a long time, the open rate was the key metric for email campaigns. It has become unreliable since email clients, Apple first among them, preload images or block them. Look instead at:

• the reply rate, and above all the positive reply rate;
• the bounce rate, which must stay low;
• the share of emails that land in the inbox rather than in spam, measured during warmup;
• the number of meetings obtained, relative to the number of people contacted.

Our article on metrics explains how to read these figures and when they start to mean something.

What to take away

There is nothing spectacular about a good email prospecting campaign. It rests on a precise target, a clean list, healthy mailboxes, a short and honest message, follow-ups that add something, and real responsiveness when someone replies. Each step on its own seems simple. What takes time is holding them all together at once, week after week.

This is exactly what we set out to automate with SmartOutbound: you connect your own mailboxes, the tool handles warmup, address verification, assisted copywriting, sending pace and reply sorting, and you stay in control of every first email. The first month is free, with no credit card required.