I’m thinking about preventing people from signing up to Feature Upvote, my B2B SaaS, if they use an email address whose domain name is known to be a disposable email service.
I think it will remove some noise in my metrics. As far as I can tell, 0% people of people who sign up with disposable email addresses have converted to paying customers.
What do you think? Have you made the same decision?
I have started doing so, the main reason was due to getting a lot of spam signups. Even with everything in place (captcha, no disposable emails, require click link in email to activate) I still get quite a few spam signups.
Yes, we have blocked them. They are only used by spammers (mostly), “security researchers” (occasionally), or by tire-kickers (rarely).
I have the same issue.
Does anyone have a list of disposable email domains?
I do not. In fact, it’s quite common (in my world) when someone signs up as name@gmail.com, working for a company N/A Yet, only to disclosure actual company email address and name later. If nothing else it is an additional testing for the service.
https://github.com/FGRibreau/mailchecker has quite a thorough database of disposable email domains.
We’re also thinking of preventing sign ups from disposable emails for our SaaS.
There seems to be several GitHub repos with lists of disposable email domains. There’s even a SaaS to check for you: https://www.block-disposable-email.com/cms/
Really, there seems to be a SaaS for EVERYTHING these days!
There’s interesting to hear. I had thought about not allowing xxx@gmail.com email addresses too, but you make a good argument for allowing them.
We block them using https://open.kickbox.io/, but it only really makes them stumble, especially when they can buy 1000 yahoo etc accounts for a few hundred dollars.
A gmail account would not normally be considered a disposable email address. I don’t block them either.
Hi Steve,
There’s a pattern I’ve seen: some analysts will use a throwaway email address to query a bunch of possible vendors only so they can avoid being marketed to. Personally, I’d like to see a checkbox along the lines of, “besides getting the information you are signing up for, do you want to hear about what we do on an ongoing basis”. If respondents uncheck the box, you will have much more credibility - and much less never-converting emails to send.
I started doing this about 2 weeks ago at Roadmap, was starting to get more and more of disposable emails.
+1 regarding not blocking @gmail.com also, someone from Slack signed up with a gmail account. But now I’m puzzled about letting disposable emails as well… hmm.
I have lots of owned domains, but I sign up everywhere using my gmail address.
Me too. Not sure why anyone would consider blocking gmail.
What is the definition of disposable email service?
For me that is a service providing email addresses automatically expiring within minutes, hours or days. - We do block these kind of addresses as our trial/signup process includes to send important info via email during the trial phase.
I do not consider gmail, hotmail, outlook, and similar services to be disposable email addresses. We have many paying customers who initially signed up for a trial using such an address. One of our customers is paying us a 3-4 digit annual amount using the hotmail address of its CEO. 
Yes, this is exactly what I meant by “disposable email service”.
We do block these kind of addresses as our trial/signup process includes to send important info via email during the trial phase.
How do you go about detecting them? Do you manually curate a blacklist of domains? Or do you use a service?
I check against an static list of disposable email domains. I think it was this one: https://gist.github.com/adamloving/4401361
Over the last 2 years or so, I manually added a couple of domains to that list manually. All in all, that is not a big deal for us. Before adding this check to our trial signup process, signups with disposable addresses where about 1-2% of the total. I do not track the number of rejects based on that list.
So weird. I was looking at this just yesterday.
I havent tested this, but https://clearbit.com/risk looked like something I needed which is definitely to stop spam signups. 50k free a month too is great.
FYI: i have removed clearbit. They flag high risk on pretty much everyone from certain countries. Alex their CEO recommended it be used with some manual validation to block spam.