Hard bounces and soft bounces in HubSpot, and what to do with bounced contacts

A hard bounce in HubSpot means the receiving server refused the email for a reason HubSpot treats as permanent, or a strict security filter blocked it. HubSpot then drops that address from future marketing emails to protect your sending reputation. A soft bounce is a temporary problem, and the contact stays eligible for your next email.

Before you do anything with a bounced contact, find out why it bounced. Open the sent email, go to the Recipients tab, click Bounced and open the contact to read the reason and the server's response. Across all your sends, the Email hard bounce reason contact property holds the same information.

Why HubSpot emails bounce

Unknown user and Mailbox full

These are the bounces where the address itself is the problem. Unknown user usually means the address is invalid, and Mailbox full means an inbox that has been inactive or over its storage limit for a long time. HubSpot drops these contacts automatically. If an address bounces for one of these reasons in three or more HubSpot accounts, it becomes a global bounce and is dropped in every HubSpot account. Read the full server response first, because HubSpot notes it can show whether an Unknown user result came from a server issue instead.

Spam, Content and Other

Spam and Content bounces mean the receiving server's filter flagged the email, because of something in the content or your sender reputation. Other covers responses too vague to sort, plus global bounces. In these cases the address may be fine. HubSpot's fix is for the contact to ask their IT team to allowlist your sending IP addresses, and then for you to unbounce them.

Policy bounces from failed authentication

A Policy bounce means the email failed one of the receiving server's security policies, which includes DMARC, DKIM and SPF failures. If you see a lot of these, check your sending domain before anything else. HubSpot says Google and Yahoo bounce bulk email from domains that don't have all three set up. There's also a soft bounce reason for your own side: "Your IT team has not authorized HubSpot to send emails on your behalf" means your company's DMARC policy needs updating to include HubSpot. The spam and authentication guide walks through the records.

Temporary problems: soft and pending bounces

A pending bounce is a temporary issue with the sending or receiving server. HubSpot keeps trying for up to 72 hours, and if the message still isn't delivered it becomes a soft bounce. Soft bounces cover overloaded or timed-out servers, a mailbox that's full for a short time, and emails rejected as too complex because of heavy HTML, images or links. These contacts stay eligible. HubSpot suggests cloning the email and sending it to them again later.

Bounces on sales emails and sequences

One-to-one emails and sequence emails go through your connected inbox. The bounce shows on the email activity in the contact's timeline with less detail than a marketing bounce, and the full bounceback arrives in your own inbox. HubSpot says it can't always identify the cause, and it doesn't detect bounces for emails sent outside HubSpot.

How to remove a hard bounce in HubSpot

Unbouncing puts a contact back on your marketing sends, so HubSpot sets conditions. As of October 2026, its unbounce article lists Marketing Hub or Content Hub Professional or Enterprise, and you need Super Admin or marketing email permissions. You also need a connected email sending domain, an email from the bounced address confirming it's valid and wants your marketing email, and the server problem behind the bounce fixed.

1. Check the bounce reason. For Unknown user, correct the address if you have the right one. Bounces belong to the email address, so a contact whose address changes is no longer treated as bounced.
2. For filter and policy bounces, open the email tool, choose Email tools, then Manage allowlisting, and copy the IP addresses. Send them to the recipient's IT team along with your sending domain.
3. Get an email from the bounced address that confirms it works and that the person wants your emails. Take a screenshot showing the sender, recipient and send time.
4. Open the contact record and click Unbounce above the contact's name. Tick I confirm that this email address is correct and click Unbounce this contact.
5. Clone any email they missed and send the clone to them. Emails dropped while the contact was bounced aren't resent.
6. Contact HubSpot Support instead if the address is a global bounce, was unbounced before, or you've already unbounced more than 1,000 contacts or 2% of your contacts this month. Send them the screenshot from step 3.

How to stop bounces building up

Turn on double opt-in for your forms so mistyped and fake addresses don't become subscribers. Don't import purchased or guessed lists. HubSpot says to delete purchased lists or import them as opted out. Build a segment with Email hard bounce reason is known, then decide whether to delete those contacts or set them as non-marketing. The Clean up contacts option on the Marketing Contacts page shows bounced and unsubscribed groups by default. After each large send, check the Hard Bounces rate on the email tool's Health tab.

From client work

In the Frontline Facility Partners outreach program, bounces kept hurting sends. Part of the weekly cycle I run for them is removing bounced contacts from HubSpot and marking them in the master lead list that feeds the sequences. Read the Frontline case study. For Mokwheel Factory Store, before emailing 2,631 subscribers who hadn't opened in a year, I removed bots and role addresses, which left 2,385 real people. Read the Mokwheel case study.

If bounces keep climbing and you can't tell whether it's the list or the domain, book a free 30-minute call and we'll go through the bounce reasons together.

Questions

Does a hard bounce delete the contact?

No. The contact stays in your CRM, but it can't receive marketing emails until the bounce is removed.

Can I unbounce contacts on a Starter plan?

HubSpot's unbounce article lists Marketing Hub and Content Hub Professional and Enterprise. If you can't unbounce a contact yourself, HubSpot's bounce types article says to contact HubSpot Support.

Do bounced contacts still count as marketing contacts?

Yes, if they're still set as marketing. Setting them as non-marketing takes them out of your contact tier from the next update date.

What if my own team's address bounced?

HubSpot users whose address hard bounced stop getting HubSpot notification emails. A Super Admin can fix this in the Users & Teams settings by choosing Unbounce email from that user's Actions menu.