What's the best ESP?


I often get clients and potential clients asking me to tell them what the absolute best ESP is.
“You’re an expert in the field, which ESP will give me the best inbox delivery?”
The thing is, there isn’t an answer to that question.
ESPs have expertise in sending large amounts of mail.  All have staff that manage and monitor MTAs. Most have staff that provide advice on delivery issues. Many have staff that handle abuse complaints, FBLs and blocks.
What they don’t have is magic delivery fairies or bat phones into postmaster desks.
Simply moving mail to an ESP won’t give you delivery. For the most part, delivery is the responsibility of the sender, whether they send mail through an in house system or through an ESP.
Delivery is primarily about how recipients react to a particular mail stream. Send mail recipients want, interact with and relate to and you usually see good delivery. The IP addresses or infrastructure contribute but do not dominate the equation. Sending from an ESP won’t fix poor content, irrelevant mail or unengaged recipients.
I can hear everyone now shouting at their screen “What about shared IPs!!!?!?!” Yes, yes, if you use an ESP with shared IP addresses and the ESP gets a bad customer you may see poor delivery for a time because one of their other customers was bad. It’s a fact, it happens. Plus, if you use an ESP with dedicated IPs and the ESP gets a bad customer you may see poor delivery for a time because one of the other customers was bad and their IP is near yours.
So clearly the answer is to bring email in house. That way no other company can affect your delivery, right? Yes. Kinda.
Are you willing to invest money in hiring email and DNS savvy sysadmins? Invest money in a MTA designed to handle bulk mail? Invest in an expert who not only understands bounce handling, but can explain to your developers what a good bounce handling system must do? Invest in someone who can manage authentication like DKIM? Who can handle delivery issues and understands how to talk to ISPs? Invest in development to write a FBL processor?
For some companies, the internal investment is the right answer, and bringing mail in house makes business sense.
For a lot of companies, though, they just want to use email to communicate with customers. They don’t want to have to invest in multiple staff members (as it’s very rare to find a single person with all the various skill sets needed) to just send a weekly newsletter, or daily sales email. They need a tool that works, they don’t need to know how to sign up for a FBL, they don’t need to know how to handle bounces. They can outsource that work and focus on the communication value.
Finding the best ESP starts with finding out how you want to use email.
Question 1: What role does email play in my business?

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  • You say: “if you use an ESP with dedicated IPs and the ESP gets a bad customer you may see poor delivery for a time because one of the other customers was bad and their IP is near yours”.
    This will happen also if you bring email in house. Unless you buy a full C-Class IPs you will have IP neighboorhoods and you can’t control them. It is even worst than using an ESP because the ESP will care of that IPs ASAP, instead your probably can’t control the IPs near your own ones.
    However you send your emails, you send them from an IP. And each IP has neighboorhoods. Using an ESP the other IPs are at least monitored and cared by expert people. If you simply use your own IP from an hosting provider then the other IPs are cared by the hosting provider. Also if you move in house you should use more than 1 IP so that you have an emergency route if your main IP is blacklisted. Most ESP do this automatically.

  • Curious if there is any more information available about IP reputation for a bad sender influencing the reputation of a neighboring IP address in a dedicated IP environment. Have had this question come up recently and would like to read more on the matter. Thank you.

  • We are an ESP since 2002; the only blacklist I know who blacklisted a whole ISP is UCEProtect (in 2006). Bytheway the impact of this blacklist on deliverability was very low and with a few bucks you could whitelist.
    Investing money in internal resources is always an option, but I believe that an ESP will always have more data, more connections, more tools and more experience to improve or solve deliverability issues.

  • FIVETEN will also blacklist whole ESPs, and I’ve observed one other blacklist doing it as well. But no top-500 ISP uses any sort of blacklist with that sort of criteria.
    Laura – great post.

  • I fully agree with the main point in the post, good deliverability is in the hands of the sender. But sending in-house does not mean that you need to invest in a whole department of specialists. For the costs that some senders pay to their ESP you can also buy the required infrastructure and hire a good delivery specialist.

By laura

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