Postmark vs Loops for Solo Developers

Quick Comparison

Postmark Overview

Postmark does transactional email better than almost anyone. Password resets arrive in seconds. Welcome emails hit the inbox, not spam. Order confirmations show up before the customer closes the checkout page. That speed and reliability comes from Postmark's strict focus: they only handle transactional and broadcast email, which keeps their sending infrastructure clean.

The API is a pleasure to work with. You verify your domain, grab an API key, and call a single endpoint to send. The documentation is thorough without being overwhelming. Message streams let you separate transactional and broadcast emails with independent deliverability tracking. The built-in template system supports variables and layouts, and the analytics dashboard gives you bounce rates, delivery times, and spam complaints at a glance.

Postmark starts at $15/month for 10,000 emails with straightforward per-email pricing beyond that. No contact-based billing, no feature gates at higher tiers. You pay for what you send.

Loops Overview

Loops is a newer email platform built specifically for SaaS companies. It combines transactional email, marketing automation, and product updates in one tool. Where Postmark focuses purely on delivery, Loops thinks about the entire email lifecycle of a SaaS user: signup confirmation, onboarding sequence, feature announcements, and re-engagement campaigns.

The visual editor for email flows is where Loops shines. You build automated sequences triggered by events (user signed up, trial ending, feature used) with a drag-and-drop builder. Each step in the flow can have delays, conditions, and branching logic. For a solo developer building a SaaS product, this means you can set up your entire email strategy in one afternoon.

Loops also handles contact management with properties and segments. You track user attributes (plan type, signup date, features used) and send targeted emails to specific groups. The transactional API sends one-off emails like password resets, but the real value is the automation layer on top.

Pricing is contact-based: free for up to 1,000 contacts, then $49/month for 5,000 contacts.

Key Differences

These tools serve different purposes. Postmark is an email delivery service. It sends individual emails fast and reliably. Loops is an email marketing and automation platform that also sends transactional emails. Comparing them directly is like comparing a courier service to a full marketing agency that also delivers packages.

Automation capabilities. Loops lets you build multi-step email sequences triggered by user events. Onboarding flows, trial-to-paid nudges, feature adoption campaigns. Postmark does not do this. With Postmark, you build automation logic in your application code and call the API at each step. Loops gives you a visual builder that handles the logic, timing, and branching.

Deliverability focus. Postmark's entire business is built on delivery speed and reliability. Every engineering decision they make serves that goal. Loops uses AWS SES for delivery under the hood, which is reliable but not as tightly optimized. For time-sensitive transactional emails, Postmark's delivery speed is noticeably faster.

Pricing model. Postmark charges per email sent. Loops charges per contact stored. If you have 5,000 contacts but only send 2,000 emails per month, Loops costs $49 while Postmark costs about $15. If you have 500 contacts but send them frequent emails, Postmark's per-email pricing may cost less. The model matters depending on your sending patterns.

Contact management. Loops tracks your users with properties, segments, and event history. Postmark does not manage contacts. It sends emails to addresses you provide. If you want to segment your users and send targeted campaigns, Loops has that built in. With Postmark, you would need a separate CRM or build that logic yourself.

When to Choose Postmark

• Transactional email delivery speed and reliability are your top priority
• You do not need marketing automation or drip campaigns
• You prefer per-email pricing over per-contact pricing
• You already have automation logic in your app and just need a delivery service
• You want the fastest possible integration with minimal moving parts

When to Choose Loops

• You are building a SaaS and need onboarding sequences, trial nudges, and product updates
• You want transactional and marketing email in one platform
• Visual automation builders appeal to you more than coding email logic
• Contact segmentation and targeted campaigns are part of your growth strategy
• You want one tool for your entire email stack instead of stitching together multiple services

The Verdict

These tools are not really competitors. They solve different problems that overlap slightly at the transactional email layer.

If you just need transactional email, use Postmark. It is faster, more reliable at delivery, and cheaper for pure transactional use cases. You will not find a better service for getting password resets and order confirmations into inboxes.

If you are building a SaaS and want to set up onboarding flows, trial conversion emails, feature announcements, and user segmentation alongside your transactional emails, Loops is worth the investment. Having everything in one platform with a visual flow builder saves real time compared to coding automation logic in your backend and pairing Postmark with a separate marketing tool.

My setup for a new SaaS: I would start with Loops. Getting both transactional delivery and marketing automation in one platform reduces complexity, and the visual flow builder means I can ship an onboarding email sequence in an hour instead of a day. If delivery speed becomes critical, like sending time-sensitive OTP codes, I would add Postmark just for those specific emails and keep Loops for everything else.