Are Cold Email Lists Opt-in or Non Opt-In?

I can’t tell you how many times we have heard the statement, “I’ve bought an opt-in list of a million contacts and I want to send a million emails a day.” There is so much wrong with this statement on so many levels. For marketers using cold data and purchased lists as a part of their overall cold email marketing strategy, there is a right way and a wrong way to go about implementing your plan. 

The first thing I want to make clear is cold email marketing works! 


Mind-blowing email marketing stats:


  • Email generates $44 for every $1 spent
  • Large scale email blast marketing campaigns can yield an average 4,300 percent ROI for U.S. businesses
  • 44 percent of email recipients sited a mass promotional email as the reason behind one or more purchases
  • 64 percent of people reported opening an email, regardless of the sender, due to the subject line.
  • Large scale email blasts have a 17 percent higher conversion value than social media marketing

But to explain it in a more practical matter, say you have a digital marketing budget of $450 a month and you are trying to decide whether to run Google Ads or deploy cold email marketing campaigns. Let’s assume your top page keyword bid is $10 a click. Over a month you will get 45 prospects to your landing page. If your sale price is $100 you will have to convert 10% of these clicks to break even and even more to see a return on your investment. As we know, because someone clicked on your link doesn’t mean they are ready to make a purchase at that moment. Now let’s take that $450 a month and purchase the minimum recommended architecture for cold emailing with Hotsol. Your plan will allow you to upload 100,000 contacts and send up to 50,000 emails a day after the warm-up period. Compare the two options, $450 a month for an audience of 45 or $450 a month for an audience or 100k that you can communicate with on a daily basis. To any smart marketer, it’s a no brainer.

Email marketing is clearly the cheapest and fastest way to grow your sales contacts, but as I mentioned before, there is a right way and a wrong way to approach it. Let’s dissect this statement. “I’ve bought an opt-in list of a million contacts and I want to send a million emails a day.” 

First of all, you can not, and I repeat, you CAN NOT buy an opt-in list. Either the recipients came to your website or landing page and explicitly gave you permission to email them by signing up and agreeing to accept communications from you or they didn’t. If your URL is and recipients signed up and gave you permission to email them they opted in. If you take that list and sell it to someone else who sells shoes, i.e., the recipients did not sign up with and explicitly give them permission to send emails. You don’t have an opt-in list. What you have is a targeted list of email addresses of people who may or may not be receptive to your products and services. According to SPAMHAUS the only time you can acquire a confirmed opt-in list is when it is transferred from one owner to another owner, exclusively, such as in a company buyout, with all the subscription agreements retained including the topic of the list. COI records should be transferred as part of the agreement. 

Secondly. You can’t start sending thousands of cold emails from day one to any ISP. This is a surefire way to get blocked and blacklisted. ISPs have limitations on how many emails they will accept from new IPs to their inboxes so they can manage the amount of email traffic being processed on their servers.  In addition, spam trappers and firewalls like SPAMHAUS, SORBS, and Proofpoint are designed to stop unsolicited mail from reaching inboxes. Your email list will contain email addresses that use a wide range of spam filters ( i.e. hard, medium, low) or no filters at all.  You may find your emails are inboxing to some ISPs and not others. There are many reasons for these issues. We dig deep into your email logs to identify and rectify them so you get more emails delivered to inboxes.

The secret to sending cold email in bulk is to start slowly and build your volume over time to increase your sender reputation and bulk email restrictions. 

  • Make sure your SPF, DKIM and DNS records are properly configured 
  • Keep your list current. Hard bounces and undeliverable addresses will cause your content to be blocked
  • Don’t email recipients who have unsubscribed from your list. 
  • Mail your list at regular intervals, at least once a week to lower complaint rates. 

Hundreds of companies trust Hotsol to deliver a large volume of cold email on a daily basis. Focus on your content and quality of your email list and let us deal with all things related to email deliverability. 

Put cold email marketing to work for your business.

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