Mass emailing: the good practices to know

Deliverability is the ability of an email to reach your recipient's inbox, and not their spam folder. It does not depend on a single setting, but on several factors: the reputation of your domain, the quality of your content, your sending habits and the tool that actually sends your messages. Most of these factors are under your control. This article explains how to optimize them, and what you cannot change.

1. The sender's reputation

It is tied to your domain name (for example cabinet.fr). Three technical settings are essential, especially if you use an email marketing tool:

• SPF: states which servers are allowed to send emails on your behalf;
• DKIM: signs each email to prove it has not been altered;
• DMARC: states what to do with an email that fails the SPF or DKIM checks.

These settings are checked once and for all with your IT manager or your hosting provider.

2. The content of the message

Good practices:

• a balance between text and images;
• a clearly visible unsubscribe link;
• a plain, personalized subject.

To avoid:

• an email made only of images;
• shortened links (bit.ly…);
• words that trigger filters: "urgent", "free", "exclusive offer";
• too many capital letters and exclamation marks.

The unsubscribe link is a legal requirement for commercial emails, and it also improves deliverability: a recipient who can unsubscribe flags your messages as spam less often.

3. Sending practices

• Segment your lists by industry or by skills: more relevant messages are opened more, which improves your reputation.
• Personalize at least the subject and the first name: this reduces spam complaints.
• Avoid Monday mornings and Friday evenings: inboxes are crowded and your messages are read less.

4. The tool that sends your emails

When you send an email from Nicoka with your connected mailbox, Nicoka prepares the message, but your email service (Microsoft 365, Google Workspace…) actually sends it. These services limit the number of messages you can send. Microsoft 365, for example, states a limit of about 30 messages per minute and 10,000 recipients per day; these limits depend on your subscription and may change. If too many recipients flag your emails as spam, your email service may also throttle or suspend your sending account.

A business mailbox is not designed for mass mailing. When the volume grows, the recipients' email services, Gmail in particular, become suspicious of the sender.

Use a dedicated email marketing tool (recommended)

Nicoka is not an email marketing tool. For mass mailings, we strongly recommend a dedicated solution (Brevo, Mailjet, Mailchimp…), to protect your reputation and keep your messages out of spam folders. If you still send from Nicoka, we advise you not to exceed 150 emails per hour, and to follow these tips:

• test the deliverability of your email on mail-tester.com;
• send in small batches rather than all at once;
• prefer a personal address (j.place@cabinet.fr) to a generic one (contact@…): recipients trust a person more.

Feed your Brevo or Mailjet lists from Nicoka

Nicoka does not send your campaigns, but it can feed your Brevo or Mailjet lists, which saves you manual exports and imports.

• The service is declared by your administrator in Settings > Administration > Inter Application > Services, with the Brevo or Mailjet type. Its configuration includes the Attribute mapping (which Nicoka field feeds which attribute of your email marketing tool).
• From a list of contacts or candidates, the Add to an email marketing list action offers two buttons. Add adds only the people you checked to the chosen list. Synchronize makes the list identical to the displayed variant: people who are not in the variant are removed from the list.
• People who opted out of bulk email are not added to the list.
• A synchronization treatment can also feed your lists in the background with your latest contacts and candidates. It is set up by the Nicoka teams: contact support if you need it.

The deliverability rules above still apply: the list is fed from Nicoka, but sending and reputation depend on your email marketing tool.

What is beyond your control

Once your email is sent, what happens to it partly depends on decisions you do not control.

• The rules of the recipient's email service: each service applies its own filters, which change constantly. Gmail takes into account signals specific to each user: is the sender in their contacts? Have they interacted with the sender's emails before? No setting on your side can influence these directly.
• The collective reputation of your provider: your emails leave from servers shared with other customers of the same provider (Microsoft 365, Google Workspace…). If other customers send spam from these servers, your reputation may suffer, even if your own practices are flawless.
• Your recipients' history: if a recipient has already flagged a similar email as spam, their email service will be more suspicious of your next emails.

You can still limit their impact: invite your recipients to add you to their contacts from the first exchange, and keep a very low complaint rate (under 0.1%). It is the best passport to the inbox, whatever the email service.

In short

Using the recruiter's mailbox for targeted emails is perfectly fine. For volume mailing, the lasting solution is a dedicated tool (Brevo, Mailjet…), while keeping your usual sender address.