About sender reputation

Article author
Kelly Sutter
  • Updated

Every email sender needs to build a good sender reputation with ISPs. Sender reputation essentially represents the trust established between your emails and ISP filters.

A reputation is built from measuring how your subscribers engage with your emails (opens, clicks, unsubscribes, and abuse complaints) and how you start sending to an ISP from a new IP (authentication, email content, list hygiene, and volume). All good sender reputation starts with a well-thought IP warmup plan and following email best practices.


How to repair sender reputation with ISPs

If you experience delivery issues, higher than normal soft bounces, or a significant decline in opens with any of these webmail providers, we recommend a gradual, targeted plan for the ISP.

It can take anywhere from weeks to months to repair a damaged reputation. Be prepared for ups and downs. It will take time for your metrics to level out. Stick with the targeted plan and keep sending to your engaged subscribers. Don’t be alarmed by high soft bounce rates; they don’t give you the whole story. Look at the previous engagement scores of the subscribers who are soft bouncing. If they weren’t interacting with your emails prior to the issues, you may not have anything to worry about.


What you should do

  1. Make sure you are following email best practices.
  2. Stop sending to the ISP to allow a break in delivery.
  3. After waiting at least one day, start sending small, targeted campaigns to the ISP in groups of less than 2,000 subscribers. Sending to your most engaged subscribers is best (3, 4, and 5 stars).
  4. Once you confirm the emails are getting to the inbox, feel free to add in New and Neutral subscribers (2 stars), as needed.
  5. It is recommended to wait 24 hours between campaigns. If you must send sooner, you should wait at least 4 hours between campaigns.



# of Subscribers for the ISP # of Campaigns # of Subscribers per Campaign
20,000 10 2,000
10,000 5 2,000
5,000 3 1,667
Less than 4,000 2 Divide in half



Useful tools in WordFly


Review your top domains

Take a look over your ISP breakdown by reviewing one of your largest lists in WordFly. On the List Summary page, open the Subscribers by top domains section. This will give you a high-level overview of which ISPs make up your list.


Segment by domain

Use WordFly segmentation to include the subscribers you want to send to. To find a specific domain or ISP, use an email data field segment to find all your subscribers. Combine other segments to target specific engagement ratings (star rating) or engagement scores. Use the ALL toggle to ensure that all of your segment requirements are met.



After applying your segment, you can export your ISP segment to use in other campaigns and segments. This can be helpful for managing the total volumes sent to specific subscribers.


Review stats by specific ISP and Engagement

  1. Go to Reporting > Export Data
  2. Select export option Subscribers by Account
  3. In the export options, include data field Email (this will be checked by default), then also include EngagementRating and EngagementScore. You could also add CrmSubscriberId for the CRM customer number.
  4. In the resulting export file, you will have all your subscribers and engagement data.
  5. Open your file in Excel or another spreadsheet program. Use the Data Filter tool to filter your subscriber address column by a specific ISP domain (for example, gmail.com). This will isolate all your subscribers at that domain. Then filter by the engagement rating column to find your 5-star engagement rating subscribers and then further filter by the highest engagement scores to find your best ones. You can use this to selectively choose who you will send to.