B2B newsletter for lead nurturing: Substack or Brevo?

In short: B2B lead nurturing needs a newsletter connected to your CRM, with segments by role and buying stage, automated sequences and consent you can prove. Substack works well for building authority with editorial content; Brevo or MailerLite, integrated with the CRM, are the right choice when the newsletter has to move contacts all the way to a sales conversation.

Key takeaways

• A B2B newsletter keeps the relationship alive with people who are not ready to buy yet: its value shows up as opportunities in the CRM, not as opens.
• Substack is an editorial channel; Brevo and MailerLite are email marketing platforms that handle segments and sequences and connect to a CRM.
• Three or four segments (role, industry, stage, interest) and three automations are enough to get started.
• Open rates are no longer reliable: clicks, replies and stage changes are what count.
• In Italy, promotional emails require prior consent; double opt-in is the simplest way to prove you have it.
• A newsletter does not replace social media: social brings in new people, the newsletter keeps them close until they are ready to buy.

B2B sales cycles are long and involve several people. Someone who downloads a spec sheet or attends a B2B webinar rarely buys straight away: they need procurement on board or next year's budget. If nobody gets in touch in the meantime, the lead goes cold and the acquisition cost is wasted.

A newsletter is the cheapest way to stay present, as long as it is connected to your sales data. The useful question is not "should we start a Substack?" but "which system takes contacts all the way to a sales conversation?". It fits the new B2B marketing priorities and the idea that in B2B relationships built over time matter more than contact volume. More on this topic in the lead generation and CRM section.

What is lead nurturing with a B2B newsletter?

Lead nurturing is the process of guiding a contact who is not ready to buy, with useful content at the right moments, until a commercial proposal makes sense. A B2B newsletter is the tool that makes it sustainable: a regular email to people at other companies who have agreed to receive it.

Three definitions to settle before choosing tools:

• Lead: a person at a potentially interested company, for whom you have at least a name, an email address and the channel they came from.
• CRM (customer relationship management): the software where contacts, companies, deals and sales activities are recorded. It is the single source of truth on who is a customer, who is in a deal and who is not.
• Double opt-in: the subscription is complete only when the person clicks the confirmation link sent by email. You know the address exists and that its owner entered it.

A creator tracks subscribers and paid memberships; a B2B company tracks how many contacts move from "interested" to "quote request" and how long that takes. That is why the email platform has to talk to the CRM.

Why run a B2B newsletter if you are already on social media?

Because an email list is an owned channel: you decide what to send, to whom and when, and the message lands in the recipient's inbox without going through an algorithm. On social media the same person sees your post only if the platform chooses to show it, and the post stays in the feed for a short time. An email stays in the inbox and can be forwarded to the colleague who has to make the decision.

That does not make social media pointless. The channels do different jobs and support each other:

• Social media (in B2B, mostly LinkedIn): getting known and reaching new people. The limit is that visibility depends on the platform and the contact is not yours.
• Newsletter: staying present with people who already know you, with longer content and engagement signals you can measure person by person. It grows more slowly and needs consent and an editorial plan.
• CRM and automated sequences: moving each contact forward and handing them to sales at the right moment. They only work if the other two channels feed them clean data.

In practice, social media brings new people to the sign-up form, the newsletter keeps them close during the months they are not buying, and the CRM tells sales when to call. For the social side, see the guide to B2B social media strategy.

There is a practical advantage too: starting a newsletter needs no technical skills. On Substack you can publish right after signing up; Brevo and MailerLite need a bit more setup (sender domain, forms, CRM connection), but you only do it once.

Substack, Brevo or MailerLite: which is best for a B2B newsletter?

If the newsletter is an editorial product signed by one person, Substack is the fastest way to start. If it has to move contacts towards a sale, you need an email marketing platform such as Brevo or MailerLite connected to your CRM.

Substack is a publishing platform: newsletter, web archive, comments and paid subscriptions. Publishing free content costs nothing, however many subscribers you have; if you switch on paid subscriptions, Substack takes 10%, plus Stripe's processing fees. From the dashboard you can filter subscribers, for example people who opened several emails in the last month, and export them as a CSV. Brevo and MailerLite are email marketing platforms: sign-up forms, custom fields, segments, multi-step automations and integrations with CRMs and e-commerce platforms.

Criterion	Substack	Brevo or MailerLite connected to a CRM
Main purpose	Publishing and growing a readership	Nurturing sales contacts with different messages per segment
Entry cost	Free for free content; 10% of paid subscriptions plus Stripe fees	Free plans with limits and paid plans based on contacts or sends (check current pricing)
Segmentation	Subscriber filters, targeted sends to filtered groups, sections	Segments built on fields, tags, behaviour and data coming from the CRM
Automation	Designed for publishing rather than conditional sequences	Sequences with delays, conditions and branches, e.g. "if they click the price list, alert sales"
CRM connection	CSV export or third-party integrations, to be checked case by case	Native integrations or API, n8n or Make, in both directions
Brand and data	The publication lives inside the Substack ecosystem	Forms on your website, sender on your domain, data synced with the CRM
When to choose it	The founder or an expert wants to build personal authority	The company wants a system that takes contacts all the way to a deal

The two can coexist: a founder-led Substack for visibility can sit alongside a Brevo or MailerLite newsletter for sales contacts. Avoid using Substack as the only home for your leads, because sales never sees the engagement data. For the rest of your stack, start with this guide to digital marketing tools for B2B.

How should you segment a B2B newsletter?

Segment by the few variables that actually change the message: role, industry, buying stage and interest. Three or four well-maintained fields beat twenty tags nobody updates.

• Role: the owner wants costs and risks, the technical lead wants specifications, procurement looks at terms and lead times.
• Industry or customer type: reseller, installer, manufacturer, retailer. Examples and case stories change.
• Stage: new contact, engaged contact, open opportunity, customer. The stage comes from the CRM.
• Interest: the product line the contact came in through (form, downloaded catalogue, page visited).

The easiest way to collect this data is to ask for one or two fields on the sign-up form (role and interest) and infer the rest from behaviour: which links they click and which pages they visit afterwards. If you work on a closed list of target companies, segmentation overlaps with account-based marketing: the same content has to be adapted for several people at the same company.

An e-commerce example. Take an online spare parts store selling to repair shops and consumers. Repair shops get price lists, stock levels and technical sheets; consumers get how-to guides and offers. When a repair shop keeps clicking on the same product line, the "interest" field updates and the CRM creates a task for the local sales rep.

What should you write in a B2B newsletter?

Content that helps readers do their job better or make a buying decision, not company news. A simple rule: every send answers a question your sales team or customer service hears often.

• How-to guides: how to choose a component, how to estimate requirements, how to prepare a specification.
• Signed opinion pieces: the founder's or an engineer's view on a change in the industry, such as a new regulation, a material or a sales channel.
• Use cases and case studies: problem, solution and result, only with real data and the customer's permission.
• Curated, annotated industry news: a few stories, each with two lines on what it changes for the reader.
• Answers to recurring objections: lead times, total cost, integration with the systems the customer already uses.
• Product news, only when it changes something for the reader, explained through a use case.

Each email has a single call to action, and in B2B the most effective one is often the lightest: "reply to this email if you want to talk about it". A reply opens a conversation and is the strongest engagement signal you can record in the CRM.

Two more details matter. The sender: a recognisable person, with name and role, works better than "Company Ltd Newsletter". The promise made at sign-up (what you write about and how often): keep it with every send, on a regular schedule. If the author is a well-known expert in the industry, the logic of B2B influencer marketing applies: authority matters more than reach.

An e-commerce example. A B2B office supplies store can alternate a guide ("how to estimate a year of consumables for 20 workstations"), a comparison between two product lines and the answer to the question customer service hears most. None of the three is a promotion, yet each leads to specific product pages, and clicks show which line interests which customer.

How do you grow a B2B subscriber list with consent?

By placing the sign-up where contacts have already shown interest and by giving them a concrete reason to leave their email. Bought lists or addresses copied from websites are not an option: besides the consent problem covered below, they hurt deliverability for every send.

• Website form: on product pages, blog articles and the thank-you page after a contact request, with a line saying what subscribers get and how often.
• Content in exchange for an email (lead magnet): a checklist, a technical guide, a specification template. The download cannot be made conditional on marketing consent: the newsletter box stays separate and optional.
• Webinars and events: an optional newsletter box on the webinar registration form or the form used at trade fairs. For how events fit into the rest of your communication, see the article on B2B events.
• LinkedIn: posts that point to the form, and the sign-up link on the profile of whoever signs the newsletter.
• E-commerce checkout: the optional, unticked box described in the consent section.
• Email signatures of sales and customer service staff: a link to the sign-up page.

Quality beats quantity: a hundred subscribers who match your ideal customer are worth more than a thousand addresses collected through a prize draw. More ways to acquire contacts are in the article on B2B lead generation solutions.

Which lead nurturing automations should you set up first?

Start with a welcome sequence, interest-based nurturing, a sales alert and re-engagement. They cover most situations and take days to build.

1. Welcome sequence (3-4 emails over two weeks): subscription confirmation and the promised content, an introduction to who is writing and what to expect, and a direct question ("What is your biggest challenge with…?") that can be answered with one click.
2. Interest-based nurturing: depending on the segment, a series of pieces that tackle typical objections such as delivery times, integration with existing systems, total cost and use cases in the reader's industry.
3. Sales alert: when a contact takes a high-intent action (clicks the price list, visits the pricing page, replies to an email), the CRM creates a task. The sales rep calls knowing what the contact has read.
4. Re-engagement: anyone with no clicks for three or four months gets one or two emails asking whether to stay subscribed. Those who do not respond leave the active list, which improves deliverability.

Once contacts pile up, an interest score (lead scoring) helps: each action is worth points, a few for clicking a guide, more for visiting the pricing page, many for replying to an email, and above a threshold the sales alert fires. Set the values together with sales and adjust them after a few months, based on which contacts actually became customers. Leave opens out of the score, for the reason explained in the metrics section.

The email platform and the CRM connect through a native integration where one exists, or through orchestration tools such as n8n or Make that move data both ways. I cover this more broadly in the guide to business process automation.

A B2B example. Take a machinery manufacturer that collects catalogue requests at trade fairs, with signed consent. Each contact enters a sequence tied to the machine line they asked about and, with the third email, gets an invitation to an online demo: those who accept become a CRM opportunity, the rest stay on the general newsletter.

How do you measure whether a newsletter generates qualified leads?

You measure it in the CRM, not in the email platform: how many subscribers become opportunities, how quickly and with what value. Email metrics tell you what to improve, not whether the channel works.

Opens are no longer reliable: Apple states that Mail Privacy Protection prevents senders from seeing whether a message was opened, so open rates are distorted. Rely on clicks, replies and website actions instead.

Metric	Where to find it	What it tells you
Click rate per segment	Email platform	Which topics each group really cares about
Email replies	Sender inbox or CRM	How strong the relationship is: in B2B this is the strongest signal
Contacts moving stage	CRM	How many subscribers become sales opportunities
Average time to opportunity	CRM	Whether nurturing shortens the sales cycle
Website enquiries from the newsletter	GA4 with UTM parameters	Which sends bring in quote requests or calls
Unsubscribes and spam complaints	Email platform and Google Postmaster Tools	Whether frequency and content suit the list

Then there is deliverability. Google requires anyone sending more than 5,000 messages a day to personal Gmail accounts to authenticate their domain with SPF, DKIM and DMARC, to offer one-click unsubscribe and to keep spam complaints below 0.30%, with a recommendation to stay below 0.10%. Few B2B senders reach those volumes, but the same rules decide whether you land in the inbox or in spam.

Do you need consent to send a B2B newsletter?

In most cases, yes. In Italy, sending promotional emails requires the person's prior consent (opt-in), even when the address is a business one; rules for business addresses can differ in other EU countries. The Italian Data Protection Authority's guidelines on promotional activities clarify a few useful points:

• addresses found in public registers, directories or on websites cannot be used for promotional emails without consent, including companies' certified email (PEC) addresses;
• the first promotional message cannot be used to ask for consent;
• the consent box cannot be pre-ticked, and marketing consent cannot be a condition for receiving the service;
• sharing contacts with third parties requires separate, specific consent.

There is one exception, known as soft opt-in (Article 130(4) of the Italian Privacy Code): you can email your own customers, at the address they gave you during a purchase, about similar products or services, provided you informed them and they did not object. Every email must offer an easy way to opt out. The exception covers people who bought from you: someone who only downloaded a catalogue still needs to give consent.

The GDPR (Article 7) also requires the controller to be able to demonstrate that consent was given. Double opt-in is not required by law, but it is the simplest way to have that proof: you record date, time, source form and confirmation click. Some platforms switch it on by default: in MailerLite, for example, new forms are created with double opt-in enabled. It also protects you from mistyped or bot-submitted addresses that hurt deliverability.

For an online store that also sells to businesses: an optional, unticked newsletter box at checkout and, if you rely on soft opt-in, a notice that lets customers refuse from the start. Check the details with your privacy advisor.

How to apply this in your company: first steps

1. Set a numeric goal: how many opportunities per quarter you expect from newsletter contacts. Record the newsletter as a source or campaign in the CRM.
2. Clean up the list: separate customers (soft opt-in), subscribers with documented consent and contacts without consent. The last group does not get the newsletter.
3. Choose the tool using the table above and connect it to the CRM: every sign-up creates or updates the contact with source, consent, role and interest.
4. Prepare an editorial plan for the first two or three months: topics taken from customer questions, one owner and a frequency you can actually sustain.
5. Turn on three automations: welcome, nurturing on the main interest and the sales alert.
6. Measure after 90 days: contacts that moved stage and time to opportunity; drop content that gets no clicks and double down on what earns replies.

In the solutions section you can see how I set up lead generation, CRM and automation for B2B and e-commerce companies.

Mistakes to avoid

• Importing lists without consent: business cards collected at trade fairs with no form, purchased lists, addresses scraped from websites. You risk fines and spam complaints.
• Sending the same newsletter to everyone: engineers and procurement stop reading within a few weeks.
• Keeping data in two disconnected places: if sales cannot see what the contact has read, nurturing never reaches the sale.
• Talking only about yourself: company news and promotions in every send. Nurturing works when each email answers a real question the reader has.
• Sending in bursts: three emails in one month, then silence until summer. A lower but steady frequency, which readers learn to expect, works better.
• Relying on social media alone: if the algorithm changes or your page loses reach, you have no direct way to reach your followers.

Frequently asked questions (FAQ)

Is Substack a good fit for a B2B company newsletter?

It works if the goal is to build authority with editorial content signed by a person, such as the founder or an in-house expert, and publishing free content costs nothing. It is a weaker fit when the newsletter has to feed your CRM with segments and automated sequences. In that case an email marketing platform such as Brevo or MailerLite connected to the CRM is the better choice.

What is the difference between a newsletter and lead nurturing?

A newsletter is a regular send that is the same for a whole list or segment. Lead nurturing is a journey: different messages depending on who the contact is, what they did and which stage they are in. The two usually work together: the newsletter keeps the relationship alive, nurturing sequences move the contact towards a sales conversation.

Do I need consent to email a newsletter to business addresses?

In Italy, yes: promotional emails require prior consent even when the address belongs to a company or is published on a website or public register. The exception is soft opt-in for your own customers, for products or services similar to what they bought, provided they were informed and did not object. Rules for business addresses can differ in other EU countries, so check the local implementation.

Is double opt-in mandatory?

The law does not require it, but the GDPR asks the controller to be able to prove consent, and double opt-in is the simplest way to do that. It also filters out mistyped or bot-submitted addresses that hurt deliverability.

How often should a B2B newsletter go out?

As often as you can sustain with genuinely useful content: for many B2B companies once or twice a month is a sensible starting point. Automated sequences follow their own timing, driven by what the contact does. If unsubscribes and spam complaints rise, send less often or narrow the segment.

Does a newsletter replace social media?

No. Social media is mainly for getting known and reaching new people; a newsletter is an owned channel that reaches subscribers directly, without depending on an algorithm. They work best together: posts point to the sign-up form and the newsletter nurtures contacts all the way to a sales conversation.

What should you write in a B2B newsletter?

Content that helps readers in their work: how-to guides, signed opinion pieces, use cases with real data, annotated industry news and answers to the objections sales hears most often. Product news is fine only when it changes something for the reader. Each email has one call to action, often simply to reply.

Sources

• Italian Data Protection Authority (Garante), Guidelines on promotional activities and spam (4 July 2013, Italian)
• Google, Email sender guidelines
• Apple, Use Mail Privacy Protection on iPhone
• Substack, How do paid subscriptions on Substack work?
• Substack, A guide to your subscriber dashboard
• MailerLite, How to use double opt-in when collecting subscribers

If you want to work out how to connect newsletter, CRM and automation in your company, book a free diagnosis.