Note: Upon her indictment on federal money laundering charges and her arrest February 8, 2022, Inc. dismissed Heather Morgan as a contributing columnist. As is our practice, we do not unpublish editorial content, and rather have added this note for full transparency.

A sales email's subject line gives recipients an initial glimpse of you and your business and, hopefully entices them to open an email. But it's the call to action (CTA) that usually determines whether someone will actually hit "reply" and write you back.

Far too often, people obsess about the former and neglect the latter, ending their email with utterly forgettable lines like, "I look forward to hearing from you" or "Let's chat soon. TTYL."

If you're ending emails with calls to action like that, you're giving your prospective customers a really bad last impression of yourself. You're also failing to provide clear instructions as to the next steps you want to take. In other words, these would-be customers have zero incentive to respond to you.

To avoid leaving these people confused, bored, or just uninterested, take the time to write crystal-clear CTAs that offer something enticing and push them to respond.   

Here are three ways to do that:    

1. Offer something of value.

Why should a prospective customer respond to you? It's not because you have a really cool demo to show them. In fact, most people have no interest in hearing about every product feature or watching an "informative" video clip. If you want to get your prospects on the phone, you need to prove they'll get something valuable to them in return for their time.

Think about how a phone call with you will improve their lives. Will it save time or money in the long run? Can it solve an especially painful business problem? Could it offer warning signs about a mission-critical issue, like security? So long as they're offering value that's relevant, any of these tactics can help build up credibility and entice your contact to respond.

2. Keep it short and simple.

It only takes seconds to lose someone's attention in a sales email. That's as true of the end of the message as it is of the opening line.

Your CTA is just a simple request. Bearing that in mind, keep yours focused and brief: "When do you have 10 minutes to discuss ideas for increasing your website traffic?"

Stick to one idea per CTA; nothing will confuse a reader and lose their attention faster than cramming multiple asks into one sentence. And limit these CTAs to one or two sentences, max. When it doubt, shorter is better.

Avoid cramming links, PDFs, or videos into the end of your email. Not only does this make the entire message look cluttered, it's also confusing. A reader won't know how to prioritize all those different asks, and when that happens, there's a high chance this confusion will make them give up on your email altogether.

3. Make sure your ask isn't overwhelming.

One of the reasons CTAs need to be simple is that it's easy to ask a prospect for too much and end up pushing them away. Potential customers receive hundreds, sometimes thousands, of emails each week. Most all of those messages ask them to schedule a call, book a meeting, watch a demo. So if you show up in their inbox asking for an unspecified amount of their time, you're only adding another burden to the pile, rather than offering value.

To avoid that, stick to very basic requests. Asking for 10 minutes of your potential customers' time is a non-threatening way to try and engage them. It's easier for people to say "yes" to something when they know they won't be stuck on the phone indefinitely.

And if they agree to this 10-minute call, honor the timeframe and don't spend an hour rambling about every feature your product offers.

Your CTA is really just another way of helping your potential customers take the next step, and another way to build up trust with them. Ultimately, the best salespeople end their emails by showing how much they can help the other person. Make sure your own CTAs reflect that, and you'll start to see response rates that match the open ones.

Want to learn more about writing seductive CTAs? Check out my new video course on email outreach with Hubspot on how to craft the perfect sales email.