> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sequenzy.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Using Subdomains for Email
> Protect your domain reputation and isolate email risks by sending from a dedicated subdomain
# Using Subdomains for Email
When setting up email sending, one of the most important decisions is whether to send from your root domain (e.g., `example.com`) or a subdomain (e.g., `mail.example.com`). We strongly recommend using a subdomain for all email sending.
## Why Use a Subdomain?
### 1. Reputation Isolation
Email reputation is tied to the domain you send from. If something goes wrong—high bounce rates, spam complaints, or a misconfigured campaign—only the subdomain's reputation is affected.
| Scenario | Root Domain Impact | Subdomain Impact |
| --------------------- | -------------------------- | ----------------------------- |
| Spam complaints spike | Your entire domain flagged | Only subdomain flagged |
| Blocklist addition | All email affected | Only subdomain email affected |
| Recovery time | Weeks to months | Days to weeks |
With a subdomain, your root domain remains pristine for critical communications like password resets, invoices, and personal emails.
### 2. Separation of Email Streams
Different types of email have different engagement patterns. Marketing emails typically have lower open rates than transactional emails. Mixing them can drag down your overall reputation.
**Recommended subdomain structure:**
| Subdomain | Use Case | Example |
| --------------------------- | ----------------------- | ----------------------------- |
| `mail.example.com` | Marketing & newsletters | Campaigns, sequences |
| `notifications.example.com` | Transactional | Order confirmations, receipts |
| `updates.example.com` | Product updates | Feature announcements |
### 3. Easier Troubleshooting
When deliverability issues arise, having separate subdomains makes it easier to:
* Identify which email stream is causing problems
* Isolate and fix issues without affecting other email
* Test changes on one subdomain before rolling out broadly
### 4. Flexibility for Future Changes
Using a subdomain gives you options:
* **Switch providers** without affecting your root domain
* **A/B test** different sending configurations
* **Sunset** a subdomain if it becomes compromised
## Choosing a Subdomain Name
Pick a subdomain that's professional and recognizable. Common choices:
| Subdomain | Best For |
| --------------- | ---------------------------------- |
| `mail` | General purpose, widely recognized |
| `email` | Alternative to mail |
| `news` | Newsletters |
| `updates` | Product updates |
| `notifications` | Transactional alerts |
Avoid generic names like `bounce`, `noreply`, or `mailer`—these can look
suspicious to spam filters and recipients.
## When to Use Your Root Domain
There are limited cases where sending from your root domain makes sense:
1. **Personal email** - If you're sending individual emails as yourself
2. **Very low volume** - A few emails per month with high engagement
3. **Already established** - You have years of good reputation on the root domain
Even then, consider the risk: one bad campaign could take months to recover from.
## Setting Up a Subdomain in Sequenzy
When you add a domain in Sequenzy, you can choose to use a subdomain:
1. Go to **Settings → Domains**
2. Click **Add Domain**
3. Enter your subdomain name (e.g., `mail`)
4. Complete DNS verification
The full sending domain will be `subdomain.yourdomain.com`.
Sequenzy suggests common subdomain names like `mail`, `news`, and `updates` to
help you get started quickly.
## Subdomain vs Root Domain Comparison
| Factor | Subdomain | Root Domain |
| --------------------------- | ----------------- | ------------------------ |
| **Reputation risk** | Isolated | Shared with all email |
| **Recovery from issues** | Faster | Much slower |
| **DNS management** | Separate records | Shared records |
| **Professional appearance** | Standard practice | Can look more "official" |
| **Flexibility** | High | Low |
## Best Practices
### 1. One Subdomain Per Email Type
Don't mix marketing and transactional email on the same subdomain. Their different engagement patterns will muddy your reputation signals.
### 2. Warm Up New Subdomains
New subdomains have no reputation. Start with low volume to engaged recipients, then gradually increase:
* **Week 1**: 50-100 emails/day to most engaged users
* **Week 2**: 200-500 emails/day
* **Week 3**: 1,000+ emails/day
* **Week 4+**: Full volume
### 3. Monitor Each Subdomain Separately
Track metrics per subdomain:
* Open rates
* Bounce rates
* Spam complaints
* Blocklist status
### 4. Keep DNS Records Organized
Document which DNS records belong to which subdomain. This prevents accidental deletions and makes troubleshooting easier.
## Common Questions
### Will emails from a subdomain look suspicious?
No. Sending from subdomains is standard practice—Gmail, Amazon, and most major companies do it. Recipients see your brand name regardless.
### Can I use multiple subdomains?
Yes! Many companies use different subdomains for different purposes. Just verify each one separately in Sequenzy.
### What if my root domain is already damaged?
A new subdomain starts with a neutral reputation. This is actually a good recovery strategy—create a new subdomain and warm it up properly while the root domain recovers.
### Do subdomains inherit root domain reputation?
Partially. Mailbox providers consider domain relationships, but subdomains build their own reputation over time. A compromised root domain can affect subdomain deliverability initially.
## Related
Set up DNS records for your subdomain
Protect your domain from spoofing