Best Free Email Marketing Software Tool of 2025

Best free email tool: 1-minute summary

The companies I’ve selected for this comparison are: (1) MailerLite, (2) Klaviyo, (3) Substack, (4) Omnisend, (5) Flodesk, (6) Brevo, (7) AWeber, (8) Beehiiv, (9) HubSpot, (10) GetResponse, (11) Mailchimp, (12) Kit, (13) Bento, (14) Constant Contact, and (15) ActiveCampaign.

3 different tools stand out: MailerLite, Klaviyo, and Substack.

• MailerLite offers 1,000 subscribers, 12,000 emails per month, and automation tools like welcome series—all on its free plan.
• Klaviyo gives full access to features but is tailored for ecommerce, especially Shopify users.
• Substack is perfect for newsletter businesesses launching newsletters but not for business campaigns.

So why not the others? Some lack a forever free plan. Kit, for example, allows up to 10,000 subscribers but forces you to promote other newsletters via opt-in forms—a dealbreaker for me. Others, like Mailchimp or HubSpot, restrict automation or heavily limit emails and subscribers on free tiers.

Free plan vs. Free trial

Not all email marketing tools provide a forever free plan (see table below).

Maximum emails and subscribers

Warning: While unlimited emails might sound appealing, it often comes with a cap on the maximum number of subscribers. In other words, if you’re restricted to 300 subscribers, you won’t be able to send an unlimited number of emails.

Additionally, check whether there are daily email-sending limits. For example, Sendinblue allows 9,000 monthly emails but restricts you to 300 per day. This means that if you have more than 300 subscribers, you won’t be able to send a newsletter to all of them on the same day.

Here’s the updated table without the second column:

Email marketing automation

Not all email marketing providers include automation features in their free plans. However, MailerLite, Klaviyo, and Omnisend offer (nearly) full access to automation tools as part of their free plans.

AWeber’s automation limit: one campaign explained

AWeber allows a maximum of one automation (referred to as a “campaign”) in its free plan. For example, if you create an email series with multiple messages for new subscribers, that counts as one campaign. However, you cannot create separate email series for different subscriber groups; you’re limited to a single email series (one campaign).

Brevo’s (formerly Sendinblue) 2,000 contacts limit explained

The most significant limitation of Brevo’s Free plan (and Starter plan) is that only 2,000 unique contacts can enter your automated workflows. Once this limit is reached, automation features will no longer function. This is not a monthly limit—it’s permanent. To remove this restriction, you must upgrade to the Business plan.

Michael, a Customer Experience Representative at Brevo, explained: “It’s a way for our users to test our automation feature without paying for it.” For instance, if five new subscribers enter your automation workflows daily, you’ll have 400 days before your automated campaigns stop working.

Remove branding

No email marketing tool allows you to remove their logo from emails, landing pages, or opt-in forms while using the free plan.

Best email marketing software

Looking for a quick overview of the best (and worst) email marketing platforms of 2025? Check out my new video below.