How to Automate Emails With Claude Code

You've built a SaaS with Claude Code, and now you want emails to go out on their own: a welcome note when someone signs up, a reminder before a trial ends, a summary every Monday. This guide shows how to automate emails with Claude Code so nobody has to press send.

It's for people who build with Claude Code but don't write code. You'll learn the two kinds of automated email, which ones most SaaS products need, what to tell Claude Code to set them up, and how to check they keep working.

What's the difference between event-triggered and scheduled emails?

Event-triggered emails go out the moment something happens in your SaaS. Scheduled emails go out at a set time, whatever anyone is doing.

Both are transactional emails: messages about one person's own account or activity, sent to that person, rather than marketing campaigns sent to a list.

Plenty of automations mix the two. A "three days after sign-up" email is scheduled: a job runs once a day and looks for people who signed up three days earlier.

Which emails should a SaaS automate?

Most SaaS products automate the same core set. Start with emails people can't do without, such as password resets, then add the ones that help them get value from your product.

For the full list, see 12 transactional emails every SaaS needs. For the right moment to send each one, see when each email should go out.

Keep automated emails about the person's account. The FTC's guidance treats emails that confirm a purchase, or update someone about their account or subscription, as transactional. If the subject line or the opening reads like a promotion, the email can count as marketing, which comes with extra rules such as an opt-out. Leave promotions out of these emails.

How do you automate emails with Claude Code?

Connect an email service once. Then describe each email to Claude Code in plain English: what it says, who gets it and when it goes out. Claude Code builds it into your project and sends you a test.

Your SaaS can't send email by itself, so it needs a transactional email service. SimpleSends connects to Claude Code through a connector, which uses MCP, a standard way for AI tools to work with other services. Like any email service, it needs a verified sending domain, and your live project uses a secret API key, a kind of password that lets your project use the service.

To connect SimpleSends:

1. Sign up on the SimpleSends website and follow the steps there to set up the email address you'll send from. To send from your own domain, this includes adding a few DNS records (settings that tell the internet how your domain works) where your domain is registered.
2. In Claude Code, open Customize, then Connectors, choose Add, then Add custom connector. Name: SimpleSends. MCP server URL: https://mcp.simplesends.com/mcp
3. When Claude prompts you to connect, log in to SimpleSends.
4. Back in the Claude Code chat, tell Claude Code: "I've connected SimpleSends for all transactional email." It takes it from there, including adding what your project needs to send email.

Next, ask for a plan before anything gets built:

Please set up the automated emails my SaaS needs. Start with a plan: list each email, what makes it send and when it goes out. Wait for my OK before you build anything.

You'll get a list you can edit and approve. Then work through the emails one at a time:

When someone signs up, send them a short, friendly welcome email with one clear next step: create their first project. Show me a preview, then send a test to me.

Claude Code writes and designs the email, connects it to the sign-up step in your project, and sends a test to your inbox. Test emails can go out from the chat while you build. Once your project is live, real emails send from the project itself, through SimpleSends, even when Claude Code is closed.

For the whole journey from plan to live emails, see transactional emails in Claude Code.

How do scheduled sends work for digests and reminders?

Scheduled emails run on a scheduled job, often called a cron job: a small task your hosting runs at set times. Each time it runs, it checks who should get an email and sends it.

Where the job lives depends on where your project is hosted. On Vercel, cron jobs are available on every plan, but how often they run depends on the plan:

Limits checked October 2026. Vercel runs these jobs in UTC, a standard world time, so ask Claude Code to convert from your local time. A daily or weekly email works fine on Hobby; anything more frequent needs Pro.

If your project uses Supabase, Supabase Cron is built into its database. Jobs can run anywhere from every second to once a year, and each run is recorded, so you can see whether it happened.

Here's a brief for a weekly digest:

Every Monday at 8am New York time, send each active user a short summary of their week: what they created and anything waiting for them. Skip people with nothing to report, and add a setting so users can switch the summary off.

Claude Code sets up the scheduled job, tells you when it will run in UTC, and sends you a sample. For what to put in a digest, see how to send a weekly summary email.

Some reminders don't need your own schedule. If you take payments with Stripe, Stripe can tell your project when a trial is about to end: three days before, by default, and you can change that in Stripe's settings. Claude Code can send your reminder when that message arrives. Stripe can also send its own reminder seven days before a trial ends, so pick one to avoid doubling up. The trial ending email guide covers what to say.

SubjectYour yourcompany trial ends in 3 days Hi Sam, Your free trial ends in 3 days. To keep your projects and settings, add a payment method before then. Add payment method → (button) If you'd rather not continue, there's nothing to do. Your trial will end on its own. The yourcompany team

How do you keep an eye on automated emails?

Ask Claude Code. With SimpleSends connected, Claude Code can read your send logs and delivery status, so it can tell you whether an email went out and help work out why one didn't.

Three habits keep automations healthy:

1. Test each email before launch. Ask Claude Code to send you a test of every automated email, with realistic names and details.
2. Check in after launch. A quick weekly question catches problems early:

Check last week's automated emails. Did the welcome emails and the Monday summary all go out? Tell me about anything that failed or bounced, and why, in plain English.

3. Look at the schedule when a whole batch is missing. If no one got Monday's summary, the job may not have run at all. Ask Claude Code to look into whether the scheduled job ran and what stopped it.

When a single user says an email never arrived, see how to check whether your emails actually sent.