How To Write Follow-up Email Subject Lines That Double Your Response Rates

It’s easy to ignore how important follow-up email subject line (and following-up, in general) is to your outreach. If you need a response from contacts you don’t know personally, you’ll have to send multiple follow-ups after getting the first email ignored. Follow-up persistence pretty much dictates sales outreach efficiency — as Robert Fillmore quotes, 96% of deals close after the 5th touch. 

Sending as much as 5 follow-ups can be long and tedious — no one wants to wait longer for something that could be accomplished earlier.

So how do you get a response (and hence close) earlier and make your sales cycle shorter? 

By tweaking your follow-up email subject line. 

Here’s why.

Why do follow-up email subject lines matter?

When your follow-up email lands in your recipient’s inbox — the subject line is the first thing they see. People with cluttered inboxes skim through the subject lines and only open emails with relevant ones. This includes your follow-up emails, which could be ignored along with hundreds of other emails. The subject line of your follow-up email drives opens and responses, based on how well you’ve crafted them.

So crafting a compelling follow-up email subject line matters if you wish to gain the recipient’s attention and response. Effective follow up email subject lines can help you spend less time waiting for a response and hence close more deals.

So let’s explore tips and tactics that can help (and hurt) you creating response inducing follow-up email subject lines.

Follow-up subject line tips to boost opens and responses

1. Be conversational

If you’re using subject lines that look promotional in nature — your recipients are likely to see through your intent. Phrases like “Last few stocks..” or “Time’s running out…” don’t do much in terms of making your prospect want to open your email. These phrases are overused and have turned email recipients blind towards them.

Instead — use phrases that would make your prospects pause and consider if they should open your email. Craft the follow-up email subject line that’s conversational in nature. It should spark a need to know more and respond to whatever it is you have to say. Example —  “Discussions concerning XYZ…” or “Next steps going ahead with…”. 

2. Keep it concise and actionable

While skimming through emails, recipients are often looking for the ones that might need immediate actionables and are urgent in nature. Only emails with subject lines that outline actionables and tasks will end up being opened and responded to in such cases. Addressing important emails in this fashion is the primary purpose behind professional email accounts — enabling your recipients to catch up on important communications and actionables. 

Naturally, any follow up email subject line that’s not framed like so will end up being ignored. To avoid this, ensure that your subject line clearly outlines what the email’s about, what you need from your recipient, and what are the next steps. Covering all or any of these in a concisely crafted subject line will make sure you grab your recipient’s attention and get them to respond and take action. 

An example for such a subject can be – “Update on pricing discussions..” or “Meeting notes and todos…”. On the opposite end – follow-up email subject lines like “Waiting for your response..” don’t follow this rule and are likely to get ignored. 

3. Experiment 

There’s a lot of scope in terms of how much you can experiment with your follow up email subject lines. The majority of subject lines aren’t very well thought out and are likely to underperform. 

Treat follow-up email subject lines like copy — by way of communicating ideas that nurture your recipient’s intent. As long as it doesn’t resemble common promotional phrases and advertising copies — crafting a good subject line for follow up email in this manner will only help you get more opens and responses over the long run.

Make it a point to measure the engagement of different approaches towards these experiments, so you can replicate and scale the results from successful ones.

One of Zenefits’ onboarding emails is a great example of this. It poses a question to which the answer is already known. The way the subject is framed gives a recipient the impression that there might be a solution to the problem mentioned in the email, i.e compliance costs. It is one of the Best subject lines for follow-up email we’ve come across.

4. Utilize snippets

Snippets, similar to the definition, are short phrases that appear beside the subject line of your email in your recipient’s inbox. They’re an extension of the subject line, helping your recipient know more about the contents of your email before they need to open them. 

Since follow-up email subject lines tend to be shorter themselves, you can leverage snippets to provide your recipients with additional phrases that complement the subject line. 

In this example, the snippet is being used to add another headline the newsletter covers, in case the one in the subject isn’t as attractive for the recipient. 

5. Frame it as a question

In continuation to the first point where we discussed being conversational with your follow up email subject line — framing questions as a subject further adds to its conversational nature. Questions in follow-up email subject lines are more likely to catch the recipient’s attention since having to answer questions poses as an actionable in itself. 

These questions can be related to the topic you covered in your previous email that went unopened or without a response, or anything else you might want to draw their attention to. Whatever it is — make sure it is relevant to your recipient, and not off-topic, in which case it’ll likely be ignored.

For example, follow-up subject lines like — “Are we clear to go ahead?” or “Are there any roadblocks/constraints..?” are great examples of this approach. The recipient will usually want to address these questions when they see these subjects pop up in their inbox.

6. Personalization is key

When you personalize your follow-up subject line with your recipient’s name, or other details specific to your recipient — it’s likely to grab their attention. You’re much more likely to get a response to your follow-up email since such a personalized email commands more attention and piques your recipient’s curiosity. 

Apart from the name, you can also personalize your follow-up email subject line using details like mutual connections, events, common topics of interest, etc. You can use tools like SalesHandy and use Merge tags to personalize and automate your follow-up emails.

Above is an example of a job interview follow up email subject line, where the interviewee has personalized the subject line with a field dedicated to the recruiter’s first name and kept it relevant with reference to a recent event, i.e. the interview. This grabs the recipient’s attention as it is directly addressed to them.

7. Address their previous objections 

If you had an engagement drop off because it wasn’t the right time for your recipient, or they didn’t have their requirements met, you can follow-up once you’ve solved for those. 

When you do follow-up, make sure your subject line clearly indicates that concerns or objections from previous threads have been addressed. Once your recipient’s notice that in your subject, they’re likely to engage back and take the conversation further.

Take an example — a subject line like “Update on our privacy features..” if the customers’ previous concern was your product’s privacy policy, is way more likely to be opened and responded to.

8. Continue on older threads

By replying on your last email — you’re bringing back your recipient’s attention to your ignored message. By doing so you also don’t have to create a new subject line for your follow-up email altogether.

Replies on old threads have the default subject line appended with “Re: ”. This is quick to grab your recipient’s attention since it implies there’s an update to an older engagement. While you’re working on an older subject line for a follow-up email, make sure the email content matches with it and is relevant for your recipient.

Swiftstack’s sales follow up email subject line is used here to bring back the recipients’ attention to their previous email using the older thread. This is a great example of a subject line for a follow-up email after no response.

Now that we’ve gone through things that will help you write better subject lines for your follow-ups, let’s explore some bad practices that you should avoid.

Follow-up subject line Don’ts

1. Spammy keywords

When you’re writing the subject for your follow-up email, make sure to avoid spam triggering words. This is true not just for the subject, but also for the email body. Email Service Providers (ESP) filter every email that’s addressed to your recipient, and ones that look spammy, don’t land in your recipient’s primary inbox.

This will significantly reduce your chances of getting a response since your emails wouldn’t be accessible – and would defeat the purpose of sending follow-ups. Example, “Free trial extension…”

2. ALL CAPS

ALL CAPS fonts are often used on informal communication channels like social media platforms to signify screaming or raising voice — which isn’t very professional to adopt into formal communications.

While it might definitely grab your recipient’s attention, writing in all caps is now frowned upon by most people. Apart from the risk of being filtered into spam – you’ll also create a bad impression for yourself to be using such tactics to grab your recipients’ attention.

Follow-up email subject lines like “40% DISCOUNTS – RESPOND NOW” are the perfect example of why you shouldn’t use this technique. They look like they need attention, and being something people see frequently, are easily ignored.  

3. Click baiting

Click baiting is the practice of crafting a title or subject that can be often enticing and sensational, where the content either doesn’t live up to the subject or is misleading. This is commonly seen among marketing and promotional emails, but for professional communications, this approach might backfire. 

Your recipients might report your emails as spam, which will harm your ability to deliver emails to your future prospects or leads. Click baiting might help you score more opens, but it will degrade your email sending capabilities along with response rates and wouldn’t benefit you in any way whatsoever.

Example, Having a subject line like “One last thing..” to attract your recipient and have them open the emails, to only have repeated the message from your previous email, will easily get you reported for spamming

4. Repeat yourself

Other than responding to old threads, you shouldn’t be sending follow-ups with the same or similar sounding subject lines all across. This will give your recipient the impression that there isn’t anything new in that conversation, which makes it easier for them to keep ignoring you.

Use different approaches and strategies at every stage in writing your follow-ups emails, so your recipients are more likely to engage knowing you have something new to talk about. 

Let’s use the subject “Can we get on a call next week?” as an example. If you’ve mentioned getting on a call in previous emails, it makes it look like you’ve nothing new to share. And since they probably already ignored the last request, they’ll ignore it this time around as well.

5. Go off-topic

Going off-topic on your follow-up email subject lines makes for another, really easy way for your recipients to keep ignoring you. At any given point during your interaction, be well researched about your recipient’s top priorities. This will help you address those priorities in your follow-ups using appropriate subject lines, which will yield much better results.

Take for example the subject line “We’d love to help you improve your productivity..”. If you were to use it in a follow-up while decreasing employee churn was your recipient’s core problem — you’ll be likely to go off track and lose your recipient’s interest from that point on.

Keep it clean and relevant

As we learned throughout the article — follow-up email subject lines can contribute quite a bit to your outreach success. There’s still a lot of scope for experimentation – as most people don’t put in enough time to create the subject line. And the fundamentals to create great ones are mostly around helping your recipients solve the right problem, being proactive to their needs, and not chasing opens and responses for the sake of  it.

We hope you gained a lot of insight from this article. What are some of the best follow-up subject lines you’re ever come across or created yourself? Let us know in the comments.