How to Send Emails from Shopify Flow Using Gmail or Google Workspace

Decide which Gmail account FlowRelay will authenticate as. For a Workspace domain, a dedicated mailbox (something like [email protected]) is the tidy choice: it keeps automated mail out of a person’s inbox and lets you manage its app password independently. For personal use, your @gmail.com address is fine for low volume.

Note the full email address now, you’ll use it as the SMTP username, and Gmail will send mail as this address by default.

Workspace note: the app-password approach below only works if your admin allows app passwords for the organization. If you’re not the admin and the app-password page turns out to be unavailable, that’s the likely reason, and you’ll need them to enable it (or fall back to OAuth or a Workspace SMTP relay, both more involved).

App passwords only exist once 2-Step Verification (2SV) is enabled on the account, so this comes first.

Sign in to the account, go to myaccount.google.com/security, find 2-Step Verification, and switch it on, following the prompts to add a phone or authenticator. Without 2SV there’s no app-password option, and since the raw account password no longer works for SMTP, there’d be no way to connect at all.

With 2SV on, go to myaccount.google.com/apppasswords (or search “App passwords” in your Google Account settings). Type a name you’ll recognize, like “FlowRelay SMTP,” and click Create.

Google shows you a 16-character password, usually displayed in four groups of four. Copy it now; it’s shown only once. When you enter it later you can include or drop the spaces, Google ignores them. This code is what you’ll use as the SMTP password, in place of your normal account password.

Gmail’s SMTP settings are the same for personal and Workspace accounts:

• Host: smtp.gmail.com
• Port: 587 (TLS/STARTTLS) or 465 (SSL), either works
• Username: your full email address ([email protected] or [email protected])
• Password: the 16-character app password from the previous step, not your account password

That’s the whole setup. (Workspace admins managing many devices sometimes use smtp-relay.gmail.com instead, but it relies on IP allowlisting and admin-side configuration that doesn’t fit a hosted app like FlowRelay well, so stick with smtp.gmail.com and an app password here.)

Install FlowRelay from the Shopify App Store and accept the requested permissions.

On first launch, FlowRelay shows a short setup checklist: set your sender name and email, connect a provider, and send a test email. The next step covers connecting Gmail over SMTP.

In FlowRelay, open Settings, find Email delivery, and click Manage providers to open the Connect email provider dialog.

Pick SMTP from the provider list and fill in: host smtp.gmail.com, port 587 (or 465), your full Gmail/Workspace address as the username, and the app password. FlowRelay tests the connection before saving it, so a typo in the app password, or 2SV not actually being on, shows up immediately rather than after your first real send.

Gmail sends mail as the address you authenticated with. If you set a different From address under Override sender, Gmail will rewrite it back to your account address unless that address is configured as a verified “Send mail as” alias in Gmail first (see the common issues below).

Click Connect. Whichever provider you connect first becomes your Primary, and FlowRelay routes all outbound mail through it. You can connect a second provider later as an automatic Fallback, which is worth doing here since Gmail’s daily sending limit is easy to reach at store volume.

Open Shopify Flow, create a new workflow, and pick a trigger (Order created is a common one to start with). Add the Send transactional email action; it shows up in the action list once FlowRelay is installed.

You’ll need to fill in a few fields on the action: an email address for the recipient (this can pull straight from the trigger, like the customer’s email), a subject line, and the body, which is the actual HTML content of the email. There’s also an optional preview text field for the snippet shown in inbox previews. For the body, you can write plain HTML or use Liquid to pull in order details, customer names, and other data from the workflow.

Save the workflow and turn it on.

Before you trust a live trigger, use the Send test email button in FlowRelay’s settings. It confirms your Gmail connection is wired up correctly and shows you where the message lands.

Once that test email arrives, run your Flow workflow under real conditions, like placing a test order, and check FlowRelay’s delivery log to confirm the email went out and see its delivery status.