A custom tracking domain lets the open, click, and unsubscribe links inside your cold emails use your own domain — for example track.yourdomain.com — instead of the shared WarmySender domain. It's a simple, one-time DNS change that makes your emails look more trustworthy to inbox providers and keeps your brand on every link. This guide covers what it is, why it improves deliverability, the exact CNAME step, how to verify it, and the safety net that keeps your campaigns sending even if the domain is ever removed or breaks.
WarmySender runs your outreach on autopilot with AI agents, across Cold Email, Email Warmup, LinkedIn, Instagram and Multichannel sequences — plus real-time email verification. A custom tracking domain applies to your cold email campaigns.
Every cold email you send can include invisible open tracking, click tracking, and a one-click unsubscribe link. Those links have to point to a web address. By default, that web address sits on a domain shared by many WarmySender customers. A custom tracking domain swaps in a small subdomain of your domain — such as track.acme.com — so the links in your emails belong to the same domain you send from.
Mailbox providers like Gmail and Outlook pay attention to whether the links inside an email line up with the domain that sent it. If you send from acme.com but your tracking links live on a shared, unrelated domain, that mismatch is a small negative signal that can nudge you toward spam. When your tracking links are on track.acme.com — clearly part of your own domain — everything matches, which looks more legitimate and helps your emails land in the inbox. As a bonus, your recipients only ever see your brand in the links, never a shared domain.
Setting this up is a single DNS record. In WarmySender:
track subdomain of your sending domain — e.g. track.yourdomain.com.track.warmysender.com.track (just the subdomain part — most DNS providers fill in the rest of your domain automatically)track.warmysender.com3600)One setting that catches most people out: if your DNS is managed at Cloudflare, make sure the new record is set to DNS only (the cloud icon next to the record should be grey, not orange). If the record is proxied, your tracking links are routed somewhere we can't confirm, and verification will keep failing no matter how long you wait. Most other DNS providers have no such toggle — if you don't see one, there's nothing to change.
Back in Settings › Tracking Domains, click Verify next to your domain. WarmySender confirms your domain is genuinely live from end to end — that the CNAME points to the right place and that your domain securely serves your tracking links — not just that a DNS record exists somewhere. When it succeeds, the status turns to Verified, and from that moment your campaigns automatically use your domain for open, click, and unsubscribe links. If it isn't ready yet you'll see Needs attention — double-check the record's name and target, give DNS a little more time, and click Verify again. Nothing checks the domain for you before that first Verify click, so a domain you added and left alone will simply sit at Not checked yet until you come back and press it.
Status meanings:
Verified status is the reliable answer, but if you'd like to see it with your own eyes, send yourself a test email from a campaign with tracking switched on. Open it, hover over any link (or long-press it on a phone) and look at the web address your browser previews at the bottom of the screen. It should start with your own tracking subdomain — track.acme.com — rather than a shared one. That's the same thing your prospects see.
Two things worth knowing. Give it a few minutes after verifying before you send your test — the switch-over isn't always instant. And this only applies to emails sent after the domain was verified: messages already sitting in someone's inbox keep the links they were sent with, so don't judge it by an older email.
This is the important part. Once your domain is Verified, WarmySender keeps quietly checking that it stays healthy. If you remove the custom domain, or its DNS is later changed or deleted so it stops working, WarmySender automatically falls back to our default domain for your tracking links and your campaigns keep sending without a hitch. A broken or removed tracking domain can never stop your emails from going out — the worst case is simply that your tracking links temporarily use our default domain again until you fix yours.
Say you send from [email protected] and want branded tracking:
track.acme.com.track.warmysender.com.track, Value = track.warmysender.com, TTL Automatic.track.acme.com — matching your sending domain. If you ever delete that CNAME, campaigns quietly revert to the default domain and keep sending.track.acme.com if you send from @acme.com — so everything lines up.track.acme.com at us, not acme.com itself. Your bare domain is where your website and your email routing live; repointing it would take your own site offline. A fresh track subdomain touches nothing else you own.No. It's an optional upgrade for deliverability and branding. Without one, your open, click, and unsubscribe links use our shared default domain, which works fine.
Exactly one CNAME record: Name/Host = track (or whatever subdomain you chose), Value/Target = track.warmysender.com, TTL Automatic or 3600. Nothing else.
If it still says Not checked yet, it's simply waiting on you — a domain is only checked when you click Verify, so nothing happens until you press it. If it says Needs attention, we looked and couldn't reach it yet. DNS can take up to 48 hours to spread, though it's usually much faster. Confirm the Name is just the subdomain (track) and the Value is exactly track.warmysender.com with no extra characters, then click Verify again.
Your campaigns keep sending. WarmySender automatically falls back to our default domain for tracking links the moment a custom domain is removed or stops working, so a broken tracking domain can never interrupt your sending.
No. It only affects links in emails sent from that point forward. Your existing stats stay exactly as they are.
Yes. Once a domain is Verified in your workspace, all of that workspace's campaigns use it automatically.
Almost always the proxy toggle. Open the record you just added and set it to DNS only — the little cloud icon beside it should be grey, not orange. When the record is proxied, your tracking links are routed somewhere we can't confirm, so verification keeps failing however long you wait. Switch it to DNS only, save, and click Verify again.
Use a subdomain like track.acme.com, and never your bare acme.com. Your bare domain is where your website and email routing live, so repointing it would take your own site offline. A new track subdomain is completely separate and doesn't affect your website, your email, or anything else you already have set up. The name doesn't have to be "track" — links.acme.com or go.acme.com work just as well.
Email us at [email protected] with the domain you're setting up. For instant answers, you can also open warmysender.com/documentation, click "Copy Prompt to Clipboard," and paste it into an AI assistant like Claude or ChatGPT along with your question.
Related: Custom Tracking Domains overview · Email Deliverability (SPF, DKIM, DMARC) · See which recipients opened your emails.