Silverpop - Breaking the Myth of ISPs, Email Throttling and the Holidays
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Breaking the Myth of ISPs, Email Throttling and the Holidays

by: Annalivia Ford (@IBMforMarketing)
08 December 2015

Recently I was asked a question that comes up repeatedly at this time of year: "Do the ISPs tighten the rules on marketers during the holidays?"

In my opinion the answer is no, they don’t. 

ISP admins are people too! They want to have a nice holiday, to eat, drink and make merry, and to spend time with their loved ones just like everyone else. While a relaxed holiday is probably a pipe-dream for most admins, making live changes to existing systems makes it even more unlikely. The last thing I can imagine them doing is increasing their workload on purpose.

The perception that ISPs are deliberately throttling email or tightening things down over the holidays is likely due to changes in the inbound mail stream – differences created by marketers who change their own behaviors during this time period.

Anti-spam and reputation systems react poorly to sudden spikes in volume, invalid users/bad addresses, spam complaints and trap hits. The holiday season creates a great temptation to make sudden changes to existing strategies, but we advise against abrupt shifts such as the following:

  • Sending to older, unengaged list segments: This creates an uptick in invalid address bounces, generates complaints, drives down reputation due to the lack of engaged recipients, and can also cause spam trap hits, which has the potential to be disastrous. Nothing will ruin a marketer's holiday like a major block listing.
  • Sending much more frequently and breaking set expectations: In my previous post, “How to Lose Previously Loyal Customer: A Holiday Email Frequency Story,” I discussed how unexpected upticks in frequency can annoy recipients, increasing unsubscribes and complaint percentage. Sending much more frequently also creates spikes in volume at the ISPs, and some of them are very sensitive to sudden changes and react by throttling and routing mail to the spam folder.
  • Sending across channels: Done haphazardly, this can create brand confusion and, if done without permission, increase complaints and drive down reputation.
  • Sending to purchased or rented lists: The results of this are similar to sending to old database segments but generally much larger in impact. The chance of hitting traps and getting blocked is greatly increased.

These behaviors are seen as outside the norm and treated accordingly – and rightly so! There’s nothing unusual about the response from ISPs in these cases.

The best things marketers can do during the holidays to avoid reputation degradation and consequent throttling or blocking by ISPs are to:

  • Rigorously follow email deliverability best practices.
  • Avoid significant changes to established email programs that would result in volumes of additional, poorly targeted mail being sent.
  • Treat customers and prospects with the same respect you would wish to get from companies you buy from yourself.
  • Be patient. Be aware everyone else in the business is dealing with similar challenges.

Remember: It takes a long time and a lot of work to fix a bad IP/domain reputation, and a very short time to destroy a good one. Respect the email ecosystem, keep the big picture in mind and it will pay off!

Related Resources:

1) Ebook: “2015 Email Marketing Metrics Benchmark Study

2) Infographic: “Building the Optimal Transactional Email

3) White Paper: “Unsubscribe Best Practices Guide: How to Decrease Database Churn and Strengthen Your Marketing Program


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