SalesThumb sends quotes, invoices, receipts, warranty PDFs, and review requests by email. By default these go through our shared sending infrastructure. If you want to send from your own domain, connect your own Resend account and verified domain as described below. SalesThumb's default sending runs through its own Google Workspace SMTP relay; Resend is the bring-your-own option (Settings → Email also has a Google Workspace connect option).
Why a custom sending domain
- Brand consistency: emails come from "quotes@yourshop.com" instead of a shared SalesThumb address
- Deliverability: dedicated reputation. Spam folders less likely.
- Reply handling: customer replies go to your inbox, not ours.
Step 1 — Create a Resend account
Sign up at resend.com. Resend has a free tier for low volume, with paid plans as you scale.
Step 2 — Domain authentication (on Resend)
Domain verification happens on Resend's own dashboard, not inside SalesThumb: in Resend, add your domain and Resend gives you DNS records (SPF/DKIM, typically a few TXT/CNAME entries) to add at your DNS provider (GoDaddy, Cloudflare, Namecheap — wherever your domain is parked). Wait for propagation, then confirm the domain shows "Verified" in Resend.
Step 3 — Create a Resend API key
In Resend: create an API key scoped to sending. Copy it (you'll only see it once).
Step 4 — Wire SalesThumb to your Resend account
Settings → Integrations → Business Texting & Email → Bring Your Own Resend. Paste your Resend API key and your From Address (e.g. quotes@yourshop.com — must be on the domain you verified in Resend). Click Connect & verify — SalesThumb checks your API key against Resend's own domain list and confirms the From Address's domain shows "Verified" there. Once connected, the card shows your From address and a Verified/Unverified domain status; use Re-verify any time to recheck.
Separately, Settings → Email Settings (Sender Configuration) is where you set the display name and reply-to address customers see — that's the branding layer on top of the Resend connection, not the domain-auth step itself.
Step 5 — Warm up the sending domain
A brand-new sending domain has zero reputation. If you blast thousands of emails on day one, a chunk will land in spam. Warm up gradually:
- Week 1: keep volume light from the new domain (mostly transactional — quotes, receipts)
- Week 2-3: ramp up gradually, add follow-ups and review-request emails to opted-in customers
- Week 4+: send normally
SalesThumb's outbound is mostly transactional (one-to-one to a real customer who's expecting it). Transactional email is generally welcomed by inboxes, so warm-up is gentler than for marketing senders.
Deliverability monitoring
There isn't a self-serve deliverability report in the shop-facing app today — the sent/delivered/bounced/complaint/open/click stats that exist are on an internal admin-only dashboard, not something you can pull up from Settings. If you suspect a deliverability problem (bounce or spam-complaint rate climbing), contact hello@salesthumb.com and we can check the numbers on our side.
If a customer's address hard-bounces repeatedly, that's usually a stale address — nothing about SalesThumb auto-suppresses future sends to it today, so it's worth pulling obviously-dead addresses (e.g. employees who left, typos) out of your customer list yourself when you notice them.
Common issues
- Verify fails / domain shows unverified — the domain isn't (yet) verified on Resend's side, or the From Address you entered doesn't match a verified domain there. Fix it in Resend first, then click Re-verify in SalesThumb.
- "From address doesn't match domain" — your From Address must be on the domain you authenticated in Resend. quotes@yourshop.com works only once yourshop.com shows Verified in Resend.
- Bounces climbing — usually means a stale list. Pull obvious dead addresses (e.g. employees who left).