The Best Affordable Email Marketing Software for Startups

how the picks were chosen

• Free plan usefulness (real send volume, not a 14-day trial)
• Cost at 1,000 / 5,000 / 25,000 contacts
• Transactional plus marketing in one tool, or a clean handoff if not
• Setup time from sign-up to first send
• Deliverability basics: SPF/DKIM/DMARC handholding
• API depth for product-driven sends

1. 01

   Loops Marketing Transactional

   best for: SaaS startups that want one tool for transactional plus lifecycle plus broadcast

   1,000 contacts and unlimited emails on the free plan. Visual editor that produces clean HTML, plus a usable API for code-driven sends. Audiences and event-based loops are first-class. The unified product means you do not pay twice and do not stitch two vendors together.

   avoid if

   Subscriber-based pricing means cost scales with contact list size, not just send volume. No SMTP relay.

   1,000 contacts and unlimited emails on the Free plan · $49/mo for 5,000 contacts · full profile →
2. 02

   Brevo Transactional Marketing

   best for: Founders that want the most generous email-only free tier

   300 emails per day permanently free. Full transactional plus marketing plus SMS. Drag-and-drop builder is workable. Inbound parsing exists if you need it. Wide payment options.

   avoid if

   UI is busy; the SMS and CRM surface area can feel like more product than a startup needs.

   300/day permanent · $8/mo for 5,000 emails · full profile →
3. 03

   Mailtrap Transactional Testing

   best for: Startups still ironing out staging-versus-production email

   Best-in-class staging inbox plus a real production sender now. Free testing tier plus 4,000/mo on production sending. Solves "does this email actually look right" before it solves "does this email convert."

   avoid if

   Marketing automation is thin; pair it with a marketing tool if lifecycle email is the goal.

   4,000/mo (sending), free testing tier · $10/mo for 10,000 testing or sending · full profile →
4. 04

   MailerSend Transactional

   best for: Mixed engineering plus marketing teams that want both API and visual builder

   3,000/mo permanent free, modern API with a clean dashboard, drag-and-drop templates. Inbound parsing supported. Sub-accounts on higher plans.

   avoid if

   Smaller ecosystem than the bigger names; fewer integrations.

   3,000/mo permanent · $28/mo for 50,000 emails · full profile →
5. 05

   Plunk Self-hosted Marketing

   best for: Founders who want the option to self-host later

   3,000/mo on hosted free plan; AGPL-3.0 licensed self-host option for unlimited send. Unifies marketing, transactional, and broadcast in one open-source app. EU hosting available.

   avoid if

   Younger product, smaller community than Loops or Customer.io. No SMTP relay.

   3,000/mo on hosted free plan · $19/mo or self-host · full profile →
6. 06

   Mailjet Transactional Marketing

   best for: EU-based startups with GDPR-sensitive recipients

   6,000 emails/month permanently free (200/day cap). EU data residency. Marketing plus transactional. Strong template builder.

   avoid if

   Daily cap on free tier hurts launch days. API ergonomics feel dated.

   6,000/mo (200/day cap) permanent · $17/mo for 15,000 emails · full profile →
7. 07

   Postmark Transactional

   best for: When transactional deliverability is the only thing that matters

   Not the cheapest but worth calling out: $15/month for 10,000 transactional emails with the highest verified deliverability in the industry. If a missed password reset costs you a customer, this is cheap insurance.

   avoid if

   No marketing automation. You will need a second tool if you want broadcast or lifecycle.

   100/mo developer plan · $15/mo for 10,000 emails · full profile →