SaaS Onboarding Emails: What to Send and When

SaaS onboarding emails are the messages a new user gets in their first days: the welcome, the nudges and the tips that help them get going. Done well, they get people to the point where your product does what they signed up for.

This guide is for founders building a SaaS with Claude Code who want new users to get value quickly. You'll get a simple five-email onboarding sequence, when to send each email, and the message that gets Claude Code to build it.

What are SaaS onboarding emails for?

SaaS onboarding emails have one goal: get each new user to their first win as quickly as possible. The first win is the moment your product does the thing they signed up for. They're not there to sell.

Say your SaaS helps freelancers send invoices. The first win is sending a first invoice. For a scheduling tool, it might be the first booking. Write yours down before anything else, because every onboarding email should move someone one step closer to it:

• One job per email. Each email asks for one thing, with one main link or button.
• Skip what's already done. Nobody should get a nudge to do something they did yesterday.
• Stop when it's working. Once someone is using your product regularly, the sequence has done its job.

What does a simple five-email onboarding sequence look like?

A simple onboarding email sequence has five emails over the first week. Three react to what the user does, and two go out on a schedule.

1. Welcome. Short and immediate. Our guides to sending a welcome email when someone signs up and these SaaS welcome email examples cover this one in detail.

2. First-step nudge. For people who signed up but stalled:

SubjectYour first invoice takes about two minutes

Hi Sam,

You signed up yesterday but haven't sent an invoice yet. Most people start with a client they bill every month.

Add a client's name and the amount, and we'll handle the layout.

Send your first invoice

Stuck on something? Reply to this email and tell us what's in the way.

The team at yourcompany.com

3. First win. Often left out. Tell them it worked ("Your invoice was delivered") and point to the next step.

4. Next-step tip. Pick the feature that makes the first win more useful, not your newest one.

5. Check-in. A short, plain message. Replies here are some of the best feedback you'll get.

Free trials also need a trial ending email, which comes later. For the full list of emails beyond onboarding, see 12 transactional emails every SaaS needs.

Triggered vs timed emails: which should you use?

Triggered emails go out when a user does something, or fails to do something by a set time. Timed emails go out a set number of days after sign-up. Use triggered emails for anything tied to progress, and timed emails for tips and check-ins.

So before any timed email goes out, your project should check it still fits that person. That's what the "Skip it if" column above is for.

Both kinds go out from your live project, not from a chat. Timed emails rely on a scheduled check in your project that runs, say, once an hour and sends whatever is due. Our guide on when each SaaS email should go out goes deeper on timing.

How do you build onboarding emails with Claude Code?

Connect an email service, then brief Claude Code on the whole sequence in one message. It plans, writes, designs and builds the emails, and sets up the triggers and the schedule.

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 who can send email for your domain) where your domain is registered.
2. In Claude Code, open Customize, then Connectors, choose Add, then Add custom connector. Fill in the fields below.
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.

A connector is a link that lets Claude Code use another service while you build. It works through MCP (Model Context Protocol), a standard way for AI tools to talk to other services. When your SaaS is live, your project sends emails through SimpleSends directly, using a secret key (an API key) and a small piece of sending code. The chat isn't involved.

Then brief Claude Code the way you'd brief a person:

I'd like an onboarding email sequence for new users. The first win is sending a first invoice. Please set up five emails: a welcome right after sign-up, a nudge on day 1 if they haven't sent an invoice, a note when they send their first one, a tip about recurring invoices on day 4, and a check-in on day 7. Skip any email that no longer fits, and stop the sequence if someone cancels. Keep each email short, friendly and focused on one action. Show me drafts of all five before you build anything.

Claude Code will usually look at your product first, then come back with drafts and a summary of when each email goes out. Ask for changes as you would with a copywriter. Once you approve, it builds them.

Then test before real users see anything:

Send test versions of all five onboarding emails to me at hello@yourcompany.com, and tell me whether each one was delivered.

With SimpleSends connected, Claude Code can send those tests from the chat and check the send logs to tell you whether each one went out. Later changes are another message, not a code change. See how to update your SaaS emails by asking Claude Code.

Where do onboarding emails end and marketing begins?

Onboarding emails help someone use what they already signed up for. Once an email's main job is promoting something new, such as an upgrade offer, a discount or a newsletter, it's marketing. Keep those out of your onboarding sequence.

This matters for more than tone. In the US, the FTC's CAN-SPAM guidance requires commercial email to include a clear way to opt out and a valid postal address. Emails that only deal with an account or a purchase someone agreed to are mostly exempt, but the FTC reads that narrowly. Emails to existing customers aren't automatically exempt, and a mixed email counts as commercial if the subject line reads like an ad or the promotion comes first.

In practice:

A few habits keep you on the right side of the line:

• Keep the help first. If an email mentions a paid plan at all, the help comes first and the subject line stays about it.
• Let people switch off tips. Account emails must always arrive, but a "stop sending me tips" link on emails 4 and 5 is good manners.
• Send marketing separately. Upgrade campaigns need consent and an unsubscribe link, and belong in a marketing email tool.

This is general information, not legal advice, and other countries have their own rules. Our guide to transactional vs marketing emails explains the difference in more detail.