The “New Inbox” Checklist: 25 Things to Verify Before Warming (Beyond DNS)

Most teams treat “new inbox warm-up” like a simple ramp-up schedule: start at 5–10 emails/day, increase gradually, and you’re good.
But if your inbox is new, your sending reputation is fragile. And the truth is: deliverability issues rarely come from one obvious misstep. They come from small “trust signals” you didn’t know you were sending, before you ever hit “send” on a campaign.
This checklist is for startups and sales teams setting up new mailboxes for outbound. It’s the stuff to verify before you begin warm-up, especially the signals that sit beyond DNS.

What “beyond DNS” really means

Yes, you still need SPF, DKIM, and DMARC. But inbox providers evaluate far more than authentication records.
They look at:

• Mailbox legitimacy (does this look like a real employee?)
• Domain history and footprint
• Sending environment consistency
• Early engagement signals
• Hidden technical markers (headers, routing, throttling behavior)
• Behavioral patterns (reply rates, deletes, spam complaints)

Warm-up works best when your inbox already looks trustworthy before it starts sending.

The 25-point “New Inbox” checklist 

A) Mailbox identity & legitimacy (1–6)

1) Use a real-person naming convention

Avoid obviously fake formats like sales@, info@, or outreach@ for cold outbound warm-up. A real name mailbox (e.g., peter@, sarah@) tends to earn trust faster.
Verify: mailbox name matches a real sender identity you can stand behind.

2) Set a consistent “From Name”

Your display name should match the mailbox identity (e.g., “Peter L.”). Don’t rotate names or use inconsistent capitalization.
Verify: From name is stable across all tools and campaigns.

3) Add a profile photo (where possible)

For Google Workspace and Microsoft 365, a sender avatar can help the mailbox look like a legitimate user account, especially early on.
Verify: sender profile isn’t blank/default.

4) Configure a clean email signature

Keep it minimal: name, role, company, website. Avoid heavy images, multiple links, or legal disclaimers during warm-up.
Verify: signature is consistent and not “salesy.”

5) Ensure the mailbox has a real inbox history

A mailbox that has never received mail can look suspicious when it suddenly starts sending.
Verify: the inbox has some inbound messages (welcome emails, internal emails, calendar invites).

6) Don’t warm up shared mailboxes

Shared mailboxes and aliases behave differently and can create confusing identity signals.
Verify: you’re warming a primary mailbox, not an alias.

B) Domain readiness & footprint (7–11)

7) Check domain age and history

Brand-new domains can work, but they’re more sensitive. If the domain was previously used, it may carry baggage.
Verify: domain isn’t recently dropped/re-registered and doesn’t have a spammy past.

8) Confirm the domain has a real website

A blank domain with no site is a classic “burner” signal.
Verify: the domain resolves to a legitimate site (even a simple one).

9) Ensure your website and email identity match

If your domain is example.io but your signature links to example.ai, that mismatch can look sketchy.
Verify: website domain and sending domain align.

10) Create basic trust pages

At minimum: About, Contact, Privacy Policy. These aren’t just for compliance, they help the domain look real.
Verify: trust pages exist and are accessible.

11) Set up consistent branded assets

Even simple consistency helps: logo, company name formatting, and sender role.
Verify: your brand identity isn’t conflicting across web/email.

C) Sending environment & infrastructure signals (12–17)

12) Avoid logging in from 10 locations on day one

Mailbox access from multiple countries/devices immediately can trigger risk systems.
Verify: initial logins are stable (one region, predictable devices).

13) Keep IP and device behavior consistent

Rapid switching between VPNs, cloud browsers, and random devices can look like account compromise.
Verify: no VPN hopping during the first 2–3 weeks.

14) Don’t connect the mailbox to 6 outbound tools immediately

Each tool may add headers, tracking, and sending patterns. Too many integrations early can create noisy signals.
Verify: start with one sending method during warm-up.

15) Check “Send mail as” / alias configuration

Misconfigured “send as” settings can cause alignment issues or confusing headers.
Verify: the mailbox sends as itself, not via odd aliases.

16) Confirm time zone and business hours

Mailbox behavior should match your team’s real working hours. Sending at 3am local time is a red flag.
Verify: mailbox time zone matches the sender’s region.

17) Make sure the mailbox isn’t hitting provider limits

Even during warm-up, some setups trigger throttling or temporary blocks.
Verify: no warning banners, bounce spikes, or “message rejected” errors.

D) Content & tracking hygiene (18–21)

18) Disable aggressive tracking during warm-up

Open tracking pixels and heavy click tracking can hurt early reputation.
Verify: warm-up emails are plain and human-like.

19) Avoid link shorteners and redirect chains

Short links and multi-hop redirects are common in spam.
Verify: links (if any) are direct and minimal.

20) Keep HTML light (or go plain text)

Warm-up isn’t the time for designed templates.
Verify: no heavy HTML, no image-only emails.

21) Don’t include attachments during warm-up

Attachments can increase risk scoring, especially early.
Verify: warm-up emails contain no attachments.

E) Engagement & behavior signals (22–25)

22) Ensure replies are possible and monitored

A mailbox that sends but never replies looks unnatural. Engagement matters.
Verify: someone can respond to warm-up threads.

23) Build a small “safe contact” list

Warm-up works best when some emails go to real people who can reply, star, and move messages out of Promotions.
Verify: you have a handful of trusted recipients (internal + partners).

24) Watch early bounces like a hawk

A few bounces on a new inbox can do disproportionate damage.
Verify: bounce rate stays near zero; fix bad addresses immediately.

25) Confirm you have a ramp plan that matches your infrastructure

New inboxes shouldn’t jump to high volume fast. Even if a tool “allows” it, inbox providers may not.
Verify: your warm-up schedule is conservative and consistent.

A practical warm-up approach (simple and safe)

If you’re a startup or sales team scaling outbound, here’s a conservative baseline:

• Week 1: very low volume, focus on replies and natural threads
• Week 2: gradual increases, keep content plain
• Week 3–4: ramp toward your target daily volume per inbox

Also: don’t overload a domain. A common safe pattern is a few inboxes per domain and low daily volume per inbox early on, then scale gradually once engagement and deliverability are stable.

Common mistakes that kill warm-up (even with perfect DNS)

• Warming up a mailbox that looks fake (no identity, no inbound history)
• Turning on tracking + links immediately
• Logging in from multiple regions/devices
• Connecting too many tools at once
• Sending too much volume too early
• Ignoring bounces and “soft” provider warnings

Warm-up isn’t just “sending slowly.” It’s proving legitimacy.

Want help setting this up correctly?

If you’re building cold email infrastructure and want to avoid deliverability landmines, book a demo and we’ll show you how to set up inboxes and domains the right way, so you can scale outbound without burning reputation.