RecurX sends your subscribers receipts, payment recovery emails, renewal reminders and, if you use them, win-back and campaign emails. This guide connects your own email provider so those emails come from your address. It takes about 5 minutes once you have an account with the provider.
Before you start: you need an account with one of the supported providers and a sending domain you have verified with that provider (the SPF and DKIM records the provider gives you). Connecting an email provider works on every plan.
How sending works without a provider
Until you connect a provider, RecurX sends your transactional emails (receipts, payment recovery, renewal reminders) from its shared address. The sender shows as your store name followed by "via RecurX".
Marketing email (campaigns and win-back emails) only sends through your own provider. Without one, those emails wait.
Step 1: Open the Email channel
- In your Shopify admin, open Apps → RecurX Subscriptions → Campaigns.
- In the Channels group, click Connect email provider on the Email card. (If you already connected a provider, the button says Manage.)
Step 2: Check your current sender
The Sending provider card at the top shows which sender RecurX uses right now:
- Shared sender · transactional only — no provider of your own yet. Receipts and reminders go out as "your store via RecurX".
- Connected — your own provider sends everything.
While you have no provider, the yellow banner Marketing email needs your own email provider is shown too.
Step 3: Pick your provider
Under Email provider, RecurX lists the four providers you can connect. RecurX sends through one provider at a time.
| Provider | Use it when |
|---|---|
| Custom SMTP | You use any SMTP server — Amazon SES, Postmark, your own mail server. Credentials only, no API key. |
| Resend | You have a Resend account. Bring your own API key. |
| SendGrid (Twilio) | You have a SendGrid account. Supports EU data residency. |
| Mailgun | You have a Mailgun account. Supports US and EU regions. |
Click Connect on the provider you use.
Tip: If RecurX can tell from your store's domain which service already sends your email, it opens that card for you and shows a note such as Your domain … already sends with … — we've selected it below. Just add your API key.
Step 4: Enter your sender identity
Under Sender identity, fill in:
- From email — the address customers see, for example [email protected]. It must be on a domain you verified with the provider.
- From name — usually your store or brand name.
- Reply-To (optional) — where customer replies go, for example your support inbox.
Step 5: Add your credentials and connect
What you enter depends on the provider:
- Resend — API key (create one at resend.com/api-keys).
- SendGrid (Twilio) — API key with Mail Send permission, and the Region (Global (default) or EU).
- Mailgun — Private API key, Sending domain (your verified Mailgun domain) and Region (US or EU).
- Custom SMTP — Host, Port, Encryption (STARTTLS (587) or TLS / SSL (465)), Username and Password.
Then click Save and connect.
RecurX checks the credentials with the provider when you save. If the provider rejects them, the error shows under the field that needs fixing. When the save works, you see Email provider settings saved. and the card shows Active.
Note: Saved keys and passwords are never shown again. To keep a saved key when you edit other fields, leave the key field blank.
Send a test email
Once the provider is connected, open its card again (click Manage). Under Send a test, enter an address in Test recipient and click Send test. The test uses your last saved settings, so save any changes first.
If the test doesn't arrive within 2 minutes, check Spam or Promotions, and check that your sending domain is verified with the provider.
The same settings under Connections
The provider cards also appear at the top of App settings → Integrations (the Connections card on the Campaigns page opens it), under Marketing and email. It is the same form — a provider you connect in one place shows as connected in the other.
Note: Klaviyo, Mailchimp, Omnisend and Postscript on that page are not email senders. They sync your subscribers and subscription events to those tools so you can build flows there. They are Forge Integrations, on the Pro plan. See Integrations.
Switch or disconnect a provider
- Switch: click Connect on another provider and save. RecurX replaces the current provider with the new one.
- Disconnect: open the connected provider's card and click Disconnect, then Disconnect provider. RecurX deletes the saved credentials. Receipts, payment recovery and renewal reminders go back to the shared sender, and marketing email stops until you connect a provider again.
Troubleshooting
- "Enter a valid sender email" — the From email is empty or not an email address.
- "API key is required" — Resend, SendGrid and Mailgun need a key the first time you connect them.
- "Test send failed" — the most common causes are a sending domain that isn't verified with the provider, an invalid or revoked API key, or a recipient address the provider rejected.
- Campaigns or win-back emails show "Waiting for an email provider" — connect your own provider; marketing email never goes through the shared sender.