Reservics sends every booking email for you out of the box. Custom SMTP replaces that shared sender with your own mail server, so confirmations, reminders and staff alerts arrive from your restaurant’s own address with no Reservics branding.
Plan: Advance Where: Reservics → Settings → Integrations → Custom SMTP
What Custom SMTP does #
By default, Reservics delivers your booking emails through its own mail infrastructure. Diners receive a well formatted email, but the sender address belongs to Reservics and a small “Powered by Reservics” line sits in the footer.
When you connect your own SMTP server and switch it on, Reservics routes every merchant email through it instead:
- Booking confirmations to the diner
- Reminder emails before the reservation
- Reschedule and cancellation notices
- Waitlist notifications, including the “a table opened up” claim link
- Staff alerts for new bookings, pending approvals and cancellations
All of them are sent from your address, with your sender name, and the Reservics footer is removed.
Nothing else changes. Templates, timing, language and the booking flow stay exactly as you configured them.
When you would use it #
You want emails to come from your own domain. bookings@yourrestaurant.com reads as your restaurant. A shared sender does not. Diners reply to the address they see, so your own address also means replies land in your inbox instead of nowhere.
You want the emails to be fully unbranded. On Advance, the “Powered by Reservics” footer disappears once your server is sending. Useful for hotel groups, franchises and anyone presenting the booking experience as their own product.
Your deliverability is managed elsewhere. If you already pay for Brevo, SendGrid, Mailgun, Amazon SES or Google Workspace and have SPF and DKIM set up on your domain, sending through that provider keeps all your mail reputation, logs and analytics in one place.
You need your own sending logs. Some teams need to prove an email was sent, or need bounce and complaint data. Your provider’s dashboard gives you that; the Reservics shared sender does not expose it to you.
Corporate policy requires it. Larger groups often require all outbound customer mail to leave through an approved relay.
Before you start #
You need an SMTP account from an email provider. Reservics does not create one for you. Have these five things ready:
- SMTP host, for example
smtp-relay.brevo.com - Port, usually
587 - Username and password given by your provider. For many providers the password is an API key or an app password, not your normal login password.
- From address, the address diners will see. Your provider must be authorized to send from that domain.
- From name, the display name, for example your restaurant’s name.
Important: your domain should have SPF and DKIM records pointing at your provider before you switch this on. Without them, mailbox providers such as Gmail and Outlook are likely to mark your booking emails as spam. Your email provider’s documentation shows exactly which DNS records to add.
Common provider settings #
| Provider | Host | Port | Encryption | Username |
|---|---|---|---|---|
| Brevo | smtp-relay.brevo.com | 587 | TLS | your Brevo login |
| SendGrid | smtp.sendgrid.net | 587 | TLS | apikey |
| Mailgun | smtp.mailgun.org | 587 | TLS | your Mailgun SMTP user |
| Amazon SES | email-smtp.<region>.amazonaws.com | 587 | TLS | SES SMTP user |
| Google Workspace | smtp.gmail.com | 587 | TLS | your Workspace address |
| Microsoft 365 | smtp.office365.com | 587 | TLS | your Microsoft address |
| Zoho Mail | smtp.zoho.com | 587 | TLS | your Zoho address |
Use port 465 with SSL if your provider recommends it. Always confirm against your provider’s own documentation, since these can change.
How to set it up #
- In your Shopify admin, open Reservics → Settings.
- Go to the Integrations tab and find the Custom SMTP section.
- Click Configure SMTP.
- Fill in the form:
- SMTP Host and Port
- Encryption: TLS, SSL or None. Choose TLS unless your provider says otherwise. Only pick None if you are on a private relay that does not offer encryption.
- Username and Password
- From address and From name
- Click Save & send test email.
Reservics saves the settings and immediately sends a test message to your shop’s email address. Check that inbox.
- Once the test arrives, switch the Custom SMTP toggle on.
That last step is the one that actually changes anything. Saving credentials does not redirect your email by itself, which means you can set everything up and verify it calmly before any diner email depends on it.
How to tell it is working #
The Custom SMTP card shows your host and port with a Verified badge once a test has succeeded. Underneath, it tells you the exact identity in use, for example “Sending as The Corner Table <bookings@thecornertable.com>“.
If the toggle is off, the card says so and tells you booking emails are still going through the Reservics mailer.
Day to day #
Editing settings. Click Edit to change any field. You can leave the password blank to keep the stored one; Reservics never shows a saved password back to you, so an empty password field means “no change”.
Testing again. Use Send test email any time, for example after your provider rotates an API key. It sends to your shop email address.
Turning it off temporarily. Switch the toggle off. Booking emails fall back to the Reservics mailer immediately, so email keeps flowing while you sort out a problem with your provider. Your credentials stay saved.
Disconnecting. Disconnect removes the stored credentials entirely. Use this when you change providers or no longer want Reservics holding them.
Troubleshooting #
“Test failed: authentication failed” The username or password is wrong. For Gmail and Google Workspace you must use an app password, not your account password. For SendGrid the username is literally apikey and the password is the API key itself. For Brevo, the SMTP key is not the same as the API key.
“Test failed: the server refused the connection” The host or port is wrong, or your provider blocks the port you chose. Try 587 with TLS, or 465 with SSL.
The test email arrives but lands in spam This is a domain reputation issue, not a Reservics issue. Add the SPF and DKIM records your provider gives you, and make sure the From address uses a domain your provider is authorized to send for. Sending as a Gmail or Yahoo address you do not control through a third party relay will usually be filtered.
The test email never arrives Check the provider’s own sending log first, as it will show whether the message left. Also confirm your shop’s email address in Shopify is correct, since that is where the test is sent.
“Save your SMTP settings before sending a test” You clicked test before saving a complete configuration. Host and From address are both required.
Emails still show the Reservics sender The toggle is off. Saving credentials and enabling them are two separate steps.
We downgraded from Advance and emails changed back Custom SMTP is an Advance feature. On a downgrade your settings are kept, but sending returns to the Reservics mailer until you upgrade again. Nothing is deleted.
