The essentials
- The best return: email shows a return on investment of 3 to 10, the highest of any channel, because sending costs almost nothing.
- The condition: a consented list, built through the site and your customers; a bought list destroys deliverability and exposes you to a penalty.
- 2026 benchmarks: a click-through rate of 2 to 5% on delivered sends, unsubscribes under 0.5%, opens now unreliable.
- The format that lasts: a monthly appointment, one subject, something useful learnt, a single call to action.
Email is digital marketing's most profitable channel and the one small businesses neglect most. The reason has less to do with its effectiveness than with its constraint: it requires a contact list built over months, whereas advertising produces visitors on day one. Once that list exists, each send costs a few euros and reaches people who already know the company. This article describes the full method, from collection to measurement. Building the list is part of a wider approach, described in first-party data.
Building the list
| Source | Expected volume | Quality |
|---|---|---|
| Customers and quotes | Every customer, systematically | The best: an existing relationship |
| The contact form | Depends on the traffic | High, an expressed intention |
| Content to download (a guide, a template, a tool) | 5 to 15% of the page's visitors | Good, to be qualified afterwards |
| A newsletter sign-up on the site | 0.5 to 2% of visitors | Variable, real interest |
| Events, trade shows, webinars | Occasional | High if the consent is clear |
| A bought or scraped list | High | None, and unlawful in B2C |
A list of 2,000 consented, active contacts produces more than one of 20,000 inert addresses: it costs less in tooling, gets better rates and protects the sender reputation on which every subsequent send's deliverability depends.
The legal framework
In B2C, prior consent is mandatory: an unticked box, the purpose stated, proof kept. In B2B, prospecting to a named professional address is possible on the basis of legitimate interest if the message concerns the recipient's professional activity, with clear information and a right to object. In every case, each message carries a working unsubscribe link, the sender's identity and a valid address. The general collection rules are in CMP for the site side.
Choosing the frequency and the format
- A regular appointment: monthly for most small businesses, twice monthly if the news justifies it. Regularity counts more than frequency: a monthly newsletter kept up for two years beats a weekly one abandoned after six weeks.
- One subject per send: something useful learnt, an answer to a frequent question, a case study, a piece of sector data. The product catalogue isn't a subject.
- A single call to action: read the article, book a slot, download the guide. Three competing proposals divide the click-through rate.
- A plain format: readable text, one image at most, visible buttons, correct display on mobile where most messages are read.
- Simple segmentation: customers, prospects, inactives; three segments handled well beat twelve abandoned. The approach is described in audience segmentation.
- Automated sequences: welcome, quote follow-up, abandoned basket, reactivation; they produce most of the result, as marketing automation.
The metrics to track
| Metric | 2026 benchmark | What it reveals |
|---|---|---|
| Deliverability rate | Above 97% | The quality of the list and the sender reputation |
| Open rate | 25 to 40% | Unreliable since the mail providers' protections |
| Click-through rate (on delivered) | 2 to 5% | The real interest metric |
| Unsubscribe rate | Under 0.5% | Above that, the frequency or the targeting is wrong |
| Conversions per send | Depends on the objective | The only metric that counts in the end |
| Return on investment | 3 to 10 | The cost of the tool and the time, against the sales |
Tracking works through tagged links so the visits and conversions appear in GA4; the convention is described in tagging your digital campaigns.
The tools and their cost
For a French small business, Brevo, Mailchimp, MailerLite or Sarbacane cover the usual needs: free up to a few hundred contacts, then €20 to €100 a month depending on the volume and the automation features. The choice comes down to three criteria: how simple it is to build messages, the presence of automated sequences, and data hosted in Europe to simplify compliance. The tool's cost stays marginal against the writing time, which is the real budget line.
The mistakes that cost dearly
- Buying a list: a high complaint rate, sender reputation destroyed, subsequent messages classed as spam, including to your real customers.
- Sending with no rhythm: three sends in January then nothing for six months; recipients forget signing up and unsubscribe.
- Talking about yourself: a newsletter announcing the company's news without teaching the reader anything loses its audience.
- Neglecting the inactives: an uncleaned list degrades the deliverability of every send; reactivate then remove after 12 months with no opens.
- Forgetting mobile: most reading happens there.
- Not measuring the conversions: a high click-through rate with no sales proves nothing.
How GreenRed helps
Rather than juggling several tools, the GreenRed action plan brings these metrics together in a single dashboard, compares them over time and tells you which actions come first. You can try it free, with no card, from the Pricing.
Frequently asked questions
Is email still effective in 2026?
Yes, it is the channel with the best return on investment, between 3 and 10, because sending costs almost nothing and reaches people who already know the company. Its constraint is building the list, which takes months.
Can you buy a list of addresses?
No. It is unlawful in B2C without consent, and counter-productive everywhere: the complaints destroy your sender reputation and push the messages meant for your real customers into spam. A list of 2,000 consented contacts beats 20,000 bought addresses.
How often should you send a newsletter?
Once a month for most small businesses, twice if the news justifies it. Regularity matters more than frequency: a monthly appointment kept up for two years produces more than a weekly one abandoned after six weeks.
Which metrics should you track for email?
Deliverability (above 97%), the click-through rate on delivered sends (2 to 5%), the unsubscribe rate (under 0.5%) and above all the conversions generated, measured in GA4 thanks to tagged links. The open rate has become unreliable.