Guest author Joshua Geake shares his concerns about the alleged super deliverability all ESPs seem to have. And with good reason, his short research shows.
Which ESP is best?
There are hundreds of companies worldwide that offer email services but how can the average company that doesn’t understand (nor wants to understand) SMTP, DKIM and FBLs know which one to go for?
Analyzing Deliverability
I analyzed a random selection of marketing emails that landed in my inbox over the past few days against SenderScore, Sender Base, Trusted Source and MxToolbox’s blacklist checker. The scores gathered from these services will give a representation of how an ESP operates.
This includes whether it follows best principles and sends authenticated emails, unsubscribes Feed Back loop (FBL) complaints etc. It will also give an indication of how an ESP’s clients behave on their shared IPs. Remember if an ESP shares its SMTP servers between its clients, your reputation and hence deliverability is shared.
| Company | Iceland | Spotify | Currys | Overclockers | Pizza Hut | Play | Phones4u |
| SenderScore | 99 | 95 | 93 | 88 | 78 | 96 | 78 |
| Sender Base | Neutral | Neutral | Good | Good | Good | Good | Good |
| Trusted Source | Minimal Risk | Minimal Risk | Minimal Risk | Minimal Risk | Minimal Risk | Minimal Risk | Minimal Risk |
| # Blacklists | 0 | 2 | 0 | 1 | 3 | 0 | 0 |
They are even on blacklists!
From this relatively fast analysis I wouldn’t want to share an IP with Spotify, Phones4U or Pizza Hut. Pizza Hut is listed on 3 separate blacklists and Spotify 2, understandable given how poorly engaging their emails are. Being blacklisted most likely suggests that sender IP either sends out to a great deal of unknown or angry recipients.
That doesn’t seem like something i’d like to pay for
Phones4U meanwhile has a relatively low SenderScore which is explained by their low accepted mail rate of only 62.6%. In other words if you share this IP with Phones4U then only 62% of your emails will be accepted by a recipient’s email server. That’s before they hit the junk filter. I wouldn’t want to pay for that.
Do-it-yourself e-mail sending
My personal preference for avoiding ESPs and doing it yourself seems to be what Play do. It’s no surprise given how many millions of emails they send out every day that they do handle everything in-house. As can be seen they achieve as good if not occasionally better stats than the ESPs. Remember, ESPs will not do things necessarily better than you could yourself.
Check, double check, reputation check
So, in summary, if you think you need an ESP, check them out before hand. If they say Pizza Hut is one of their clients (and they no doubt mention how their conversion’s increased 450%) then sign up to Pizza Hut’s newsletter and check out their IP reputation for yourself. Unsubscribe and see how long it takes for you to be unsubscribed. Being locked into a long term contract with a careless or massively shared ESP must be really crap.
Does your ESP get you blacklisted? What are you doing to prevent reputation damage? Please share your comments.
