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Setup Guide

Email Routing & Multi-Domain Setup

Sonny supports two approaches for routing incoming emails to the right source. Choose the one that fits your email infrastructure.

Dedicated email per source

Each source has its own forwarding address

Every source in Sonny gets its own unique email channel with a forwarding address like acme+support@usesonny.email. You set up forwarding from each domain's mailbox to its dedicated Sonny address.

How to set it up

1

Create a source for each domain (e.g. "Main Site", "Secondary Site")

2

Each source automatically gets its own email channel with a unique forwarding address

3

Set up email forwarding in each domain's email provider to the corresponding Sonny address

4

Emails arrive and are routed to the correct source automatically

Example
Email flowSonny addressRouted to
support@maindomain.comacme+support@usesonny.emailMain Site
support@secondary.comacme+secondary@usesonny.emailSecondary Site

Shared forwarding with alias domains

Multiple domains, one forwarding rule

If you use Google Workspace alias domains, Microsoft 365 shared mailboxes, or any setup where multiple domains forward to a single mailbox, you only need one forwarding rule. Sonny reads the original To address from the email headers to route each message to the right source.

How to set it up

1

Create a source for each domain (e.g. "Main Site", "Secondary Site")

2

Set up email forwarding from your primary mailbox to a single Sonny address

3

On each source's Email tab, add the domain that should route to it

4

Verify you own the domain: add a small TXT record to your domain's DNS settings, or have a 4-digit code emailed to an address at that domain

5

Once verified, Sonny checks each email's original To address and routes it to the matching source

Example — one Google Group forwarding to Sonny
Email flowSonny addressRouted to
customer → support@maindomain.comacme+support@usesonny.emailMain Site (via email domain match)
customer → support@secondary.com → support@maindomain.comacme+support@usesonny.emailSecondary Site (via To header)
customer → support@third.com → support@maindomain.comacme+support@usesonny.emailThird Site (via To header)

How domain matching works

When an email arrives at your Sonny forwarding address, the routing logic works in this order:

1

Match the Sonny forwarding address

The email channel is identified by the destination address (e.g. acme+support@usesonny.email). This determines the workspace.

2

Check the original To header

Sonny reads the original recipient from the email's To header (preserved even after forwarding) and extracts the domain.

3

Match domain to source

If a source in the workspace has this domain among its verified domains, the conversation is routed there. Otherwise, it falls back to the email channel's default source.

Important

Domain matching only works when the original To header is preserved by your email provider during forwarding. Most providers (Gmail, Outlook, Zoho) preserve this header by default. If you use a mailing list or forwarding service that rewrites the To header, you'll need to use the dedicated email approach instead.


Send from your own domain

By default, replies are sent from a managed @usesonny.email address. To send as your own domain (e.g. support@yourcompany.com), verify the domain on the source's Email settings. We register it with our email provider and show you the DNS records to add:

  • DKIM — three CNAME records. Once these verify, your mail is cryptographically signed as your domain and sending turns on automatically.
  • SPF — an MX and TXT record on a mail. subdomain so SPF aligns with your domain.
  • DMARC — a recommended _dmarc TXT record so inbox providers know your authentication policy.

Use Check sending status after adding the records — DNS changes can take a little while to propagate. DKIM alone is enough to pass DMARC; SPF and DMARC add extra deliverability margin.


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