Cold Email · · 3 min read

Hard Bounce Vs Soft Bounce Emails: What's The Difference?

An email bounce can occur for a variety of reasons. Depending on the type, it can negatively affect email deliverability and become a real issue for email marketing campaigns.

hard bounce vs soft bounce

When it comes to cold outreach campaigns having a good sender reputation and maximum deliverability is key, two things a high email bounce rate can negatively impact.

Email bounces come in two main types, soft bounces and hard bounces. In this article, you will learn all about:

  • What Email Bounces Are
  • The Differences Between a Hard Bounce vs Soft Bounce
  • How to Avoid Email Bounces Altogether

What Is an Email Bounce?

An email bounce occurs when a sent email does not successfully get delivered to the recipient address, hence the sent email gets “bounced back.”

An email bounce can happen for a variety of reasons and results in a Non-Delivery Report (NDR) that is automatically generated by the sender’s mail server to inform them of the failed delivery.

Soft Bounce vs. Hard Bounce: What's The Difference?

Once an email bounces, the resulting NDR will include information that can help identify the mail server behind the rejection, why the bounce occurred, and if it was a soft bounce or a hard bounce.

Soft Bounce

A soft bounce indicates that the message arrived at a valid email address but was rejected by the receiving mail server due to a temporary issue.

The common reasons for a soft bounce are:

  • Technical server issues i.e. the receiving mail server was down.
  • The recipient’s mailbox is full and cannot accept new emails.
  • The size of the sent message is too large for the recipient’s inbox.
  • The recipient’s email security filter rejected the message.

Email providers will often continue to try and resend a soft-bounced message over the period of 72 hours.

Hard Bounce

A hard bounce happens because of a permanent issue such as sending a message to an invalid, fake, or non-existent email address.

When a hard bounce occurs it’s important to remove the fake or invalid email address from your list. Minimizing hard bounces is a priority because an email bounce rate above 2% will start to cause deliverability issues and harm your sender reputation.

Unlike with a soft bounce, your email provider will not attempt to resend messages to an invalid email address.

How to Improve Your Bounce Rate

Keeping both hard and soft bounces to a minimum is crucial to preserving your sender reputation and deliverability. And thankfully, there are steps you can take to boost both.

Email Warm Up

Warming up your email involves using it normally for a period of time to increase deliverability. Having regular email conversations, signing up to websites, and subscribing to newsletters are all ways to warm up an email.

To lessen soft bounces due to security filters, you can automatically warm up your email with to save time and optimize outreach deliverability.

Keep Your List Clean

When dealing with a large email list, it’s not unusual to have a few or even many fake ones mixed in. There are free and paid bulk email verifiers you can use to make sure you’re only reaching out to valid emails.

Verifying email lists beforehand is a great way to minimize or even eliminate hard bounces, which have a heavier impact on reputation.

Send Confirmation Emails

If you’re generating leads through email opt-ins, sending an email confirmation to subscribers will keep your list free of fake emails. Emails that don’t confirm their subscription will be automatically discarded, leaving you with a clean list to work with.

Actively Monitor Bounce Rates

Keeping an eye on bounce rates and acting quickly can help keep it at a minimum. If there are emails that result in frequent soft bounces, it’s a good idea to remove them from your list altogether. Emails that result in a hard bounce should be removed on the spot.

You can also use email automation tools to help automate actions when confronted with an email bounce to keep your list clean on autopilot.

Key Takeaways

Low email bounce rates are key to a healthy sender reputation. While consistent hard and soft bounces can negatively affect deliverability, there are plenty of tools and techniques to minimize both.

When looking to keep a low bounce rate, remember:

  • Soft bounces are due to temporary issues.
  • Hard bounces occur by sending emails to invalid or fake addresses.
  • You can use tools to verify your email list before starting outreach.
  • Having double opt-ins to confirm subscriptions will keep your list clean with warm leads.

Read next

10x your leads, meetings and deals.

Instantly scales your outreach campaigns with unlimited email sending accounts, email warmup, B2B lead database and generative AI