The Ultimate Key to Email Marketing Effectiveness Jessica Lunk As a small business marketer, you already know that email marketing drives revenue. That’s why you spend lots of time crafting enticing email messages that speak to your prospects. However, while we often dedicate a hefty helping of TLC to email copy and design, it’s easy to overlook the ultimate deciding factor in getting your emails read: A squeaky clean email list.A catchy subject line that gets clicked, a sleek HTML email template that’s easy on the eyes, and an irresistible call-to-action can’t do their job if your email never gets delivered in the first place.The Low Down on Dirty Email AddressesData decay and human error both contribute to inaccurate, undeliverable email addresses that clutter up your email list or small business CRM.So how bad is it? According to Experian, US companies believe that 25% of their data is inaccurate. Yikes. That’s a quarter of sent emails that never even see an inbox.Okay, so maybe some addresses slip through the cracks. That’s alright. Those were probably bad eggs anyway, right?Actually, those dirty addresses not only affect the contacts with bad email addresses, but they affect the deliverability of your entire list. A Good Business Reputation Relies on a Clean Email ListLet’s break it down.ISP: Internet Service ProvidersDomain name: The address of your site (meant for humans) that points to your IP addressInternet Protocol (IP) Address: An address (meant for computers) that corresponds to your domain nameSender Reputation: The score ISPs use to rate the sending behavior of IP addresses. The ISPs then filter emails from the IP address accordingly.In the world of email deliverability, the lower your sender reputation score, the more likely it is that the ISPs will filter your emails right into a spam folder, or even block them from delivery entirely.Bad email addresses = suspect sending behavior = lower sender reputation = low delivery for your entire list.In short, bad email addresses are an equation for disaster.The repercussions can be significant. Bad deliverability means that you’re missing out on opportunities to connect with marketing leads and generate revenue for your business. It also interferes with your ability to communicate with current customers, resulting in poor customer service. It doesn’t take long for a bad email reputation in the virtual world to tumble into a bad reputation in the real world. 3 Factors that Affect Email DeliverabilityThere are three buckets to keep an eye on when optimizing email delivery:Inaccurate email addresses that contain typos cannot be delivered to.Inactive subscribers who don’t open or engage with your emails.Opt-out requests that do not wish to receive your messages any more.How to Keep Your Email List Squeaky CleanGet smarter about capturing contact data. Providing a double opt-in ensures that those on your list truly want to receive your emails, and offers a check-point for deliverability. By using opt-in best practices, you build a highly targeted email list, increasing engagement and deliverability.Validate email addresses before sending to a list to avoid hard bounces.Continue to monitor bounces and unsubscribes as you send to your active email list. Make sure to remove hard bounces and unsubscribes from future mailings to keep engagement rates high.Respect opt-outs and inactive contacts. Do not continue to send email to your opt-outs, and cleanse inactive contacts (those who have not engaged with your emails for a time) from your list to increase engagement and decrease spam complaints.For many marketers, email copy and design that converts is the fun part of email marketing. But don’t forget about the foundation of great email marketing campaigns – they all rely on a clean, deliverable email list. Sending to an accurate, active and engaged audience is the best way to keep the ISPs happy and avoid the spam folder.