HubSpot Email Deliverability: The Complete Guide (2026)

Your HubSpot campaign report looks healthy. Opens are fine, clicks are fine, and the send says “delivered” on almost every contact. Then the replies dry up, the pipeline gets quiet, and a colleague tells you your newsletter has been in their spam folder for a month.

HubSpot email deliverability is hard to see from inside HubSpot, because the dashboard measures what happened after an email was accepted, not where it landed. This guide covers everything that decides whether HubSpot mail reaches the inbox, for both Marketing Hub and Sales Hub, in the order you should fix it.

Why HubSpot Email Deliverability Is Really Two Problems

HubSpot sends email two different ways, and they fail for different reasons.

Work out which path your problem is on first. Fixing the Marketing Hub sending domain will not help a Sequence that is failing from a cold mailbox, and the reverse is also true.

How to Check Your HubSpot Deliverability

HubSpot shows delivered, opened and clicked. None of those tell you whether an email reached the inbox. A message can be delivered to the spam folder, and open rates are inflated by Apple Mail Privacy Protection, which pre-loads images whether or not a person reads the email. The caveat is that open rate is still useful as a trend within one list, just not as a deliverability measure. The Apple Mail Privacy Protection guide explains the effect.

To see placement you need an outside signal:

• Google Postmaster Tools shows Gmail spam rate and authentication pass rates, published 24 to 48 hours late. See the Google Postmaster Tools guide.
• Seed mailbox testing sends your real campaign to test inboxes and reports Inbox, Promotions or Spam per provider. InboxEagle’s seed panel covers Gmail, Yahoo, AOL and Outlook. The seed testing vs inbox monitoring comparison covers when each is the right tool.
• A blocklist check on your sending domain and IP, using the free email blacklist checker.

If you only want a quick read on your setup, the email deliverability checker is free and needs no account. Domain and sender reputation behave differently, so it also helps to read how sender reputation scores work.

Set Up SPF, DKIM and DMARC in HubSpot

Authentication is the floor, not a placement guarantee. A fully authenticated sender can still land in spam on a bad list, but an unauthenticated one is rejected or filtered before content matters. For the underlying concepts, read SPF, DKIM and DMARC explained.

Connect your sending domain

In HubSpot, connect the domain you send from. Per HubSpot’s documentation, DNS changes usually take between 10 and 70 minutes to apply and can take up to 48 hours, and HubSpot suggests waiting at least 20 minutes before you verify. Use a subdomain that matches your From address, such as mail.yourbrand.com. The email subdomain strategy guide covers how to choose one.

If your DNS host is Cloudflare, HubSpot’s guidance is to turn off domain-wide CNAME flattening and proxying for the DKIM records before you verify.

SPF in HubSpot

SPF is a TXT record that lists who may send for your domain. The rule that trips people up is that a domain can only have one SPF record. If you already have one for Google Workspace or another tool, add HubSpot’s include to that record instead of publishing a second. Two SPF records both fail. Check the result with the free SPF record checker, and read about the 10 lookup limit if you send from several tools.

DKIM in HubSpot

HubSpot’s DKIM setup uses two CNAME records. Once they validate, HubSpot signs your marketing email with a key tied to your domain. Confirm it with the DKIM record checker. If it fails, the DKIM failing fix walks through the usual causes.

DMARC and alignment in HubSpot

DMARC passes when SPF or DKIM passes and aligns with the domain in your From address. For HubSpot, DKIM alignment is usually the check to get right first. HubSpot recommends relaxed alignment for both adkim and aspf. Start with a monitoring policy of p=none, confirm every sender aligns, and then move toward enforcement. The guide to moving DMARC to enforcement covers the sequence, and the free DMARC record generator builds the record. If DMARC is already failing, use the HubSpot DMARC failing fix.

Paste your sending domain here to see what your records say right now:

Shared IP vs Dedicated IP in HubSpot

Without the add-on, marketing email from HubSpot goes out over shared IPs, which means other senders on those IPs affect your placement. HubSpot sells a dedicated IP add-on for high-volume senders who want control over IP reputation. HubSpot’s documentation describes a warm-up of about 40 days, with traffic split between the shared network and the new IP, and says the warm-up pauses if you stop sending for more than seven days.

The caveat is that a dedicated IP only isolates you. It cannot repair a weak domain reputation or a poor list, and a low-volume sender on a fresh dedicated IP often does worse than on a shared pool. The dedicated vs shared IP comparison shows when it pays off, and IP reputation vs domain reputation explains which one the mailbox providers weigh most.

HubSpot Bounces: Hard, Soft and What to Do

A hard bounce is a permanent failure, such as an address that does not exist. A soft bounce is temporary, such as a full mailbox. Hard bounces are the ones that damage reputation, because mailing dead addresses signals poor list quality. The hard vs soft bounce guide lists the reasons behind each.

What to do in HubSpot:

1. Review hard bounces after every send and confirm they are suppressed from future mailings.
2. Validate any list before importing it. A spike right after an import almost always traces back to the list, and the bounce rate spike guide walks through the diagnosis.
3. Suppress contacts that soft bounce repeatedly.
4. Track the number over time with the bounce rate calculator.

If your rate is already high, follow the HubSpot high bounce rate fix.

List Hygiene: Graymail, Unengaged Contacts and Imports

Mailbox providers watch engagement. Mailing people who never open teaches them your mail is unwanted.

• Graymail suppression. HubSpot can exclude contacts who are not engaging, using the “Sends since last engagement” property. Turn it on, and note that HubSpot says suppression is less accurate if open and click tracking is off.
• Unengaged contacts. HubSpot’s reputation repair plan advises limiting sends if your cumulative open rate consistently falls below 10%, and never mailing contacts who have not opened in over a year. The caveat is that, because of Apple Mail Privacy Protection, a contact who “opens” may be a machine, so use clicks and replies as a second signal.
• Double opt-in. HubSpot recommends it on forms to keep fake and mistyped addresses off your list.
• Purchased lists. They carry spam traps and no consent. Read why purchased lists wreck deliverability.

For a full process, see email list hygiene for deliverability, and run the free list health estimator on your current list.

Why HubSpot Emails Go to Spam: A Diagnostic Checklist

Work down this list in order. Each step is cheaper than the next.

1. Is the sending domain connected and passing SPF, DKIM and DMARC? If not, fix this before anything else.
2. Did bounces or complaints jump after a specific send or import? Find the campaign and the list behind it.
3. Are you mailing contacts who stopped engaging? Suppress them.
4. Are you on a blocklist? Use the blocklist checker.
5. Does the content read as promotional? Test it with the spam word checker and the email spam tester. Content rarely decides placement alone, as content signals vs reputation explains.
6. Is it one provider or all of them? Gmail-only problems point to Gmail reputation. See provider-specific inbox placement.

The HubSpot emails going to spam fix has a step-by-step version for your account.

HubSpot Sales Hub Sequences and Cold Outreach

Sequences send through the Gmail or Microsoft 365 inbox you connect, so the mailbox itself is the sender. That changes the risks.

• Two limits apply at once. HubSpot caps Sequences at 500 emails per day on a Sales or Service Professional seat and 1,000 on an Enterprise seat, over a rolling 24 hours. Your email provider’s own cap also applies, and HubSpot cannot override it. The lower number is your real ceiling.
• Bulk enrollment is throttled. HubSpot sends a maximum of three Sequence emails per minute when you enroll contacts in bulk.
• A cold mailbox is the usual culprit. A new inbox has no sending history. Ramp volume slowly, using the email warmup planner, and read why warm-ups fail.
• Cold outreach draws complaints. Keep lists targeted and include a clear way to opt out. The cold email checklist covers the basics.

The caveat is that these limits are published by HubSpot and your provider and change over time, so confirm the current figures in HubSpot’s documentation before you plan volume around them.

The Gmail, Yahoo and Outlook Bulk Sender Rules

The rules apply to the mail you send, whatever tool sends it. Gmail and Yahoo introduced them in 2024, and Outlook followed in 2025. In summary, bulk senders need SPF, DKIM and DMARC, an easy way to unsubscribe, and low spam complaint rates. Google lists a spam rate below 0.30% as a requirement and recommends staying below 0.10%, and non-compliant traffic can face temporary or permanent rejection. Check the details on Google’s sender requirements and Yahoo’s sender best practices.

For HubSpot, that means a connected sending domain with aligned authentication, working unsubscribe links on marketing email, and a watch on complaint rate. Our Gmail bulk sender requirements guide and spam complaint rate explainer cover the thresholds in more depth.

So What Do You Actually Do?

1. Connect your own sending domain and confirm SPF, DKIM and DMARC pass and align.
2. Turn on graymail suppression and stop mailing contacts who have not opened in over a year.
3. Remove hard bounces after every send and validate imports before you mail them.
4. Stay on shared IPs unless you have the volume to justify a dedicated one, and plan the 40-day warm-up if you do.
5. Warm up every connected inbox before using it for Sequences, and respect both sets of daily limits.
6. Measure placement, not opens. Use Postmaster Tools and seed testing so you see Inbox, Promotions and Spam.

The Bottom Line

HubSpot email deliverability comes down to three things you control: an authenticated sending domain, a clean and engaged list, and sensible volume on whichever sending path you use. HubSpot gives you the controls, but its reports cannot tell you where an email landed.