68 Follow-Up Email Subject Lines to Use for Successful Campaigns

Andy Cabasso

March 4th

Did you know female mayflies are believed to have the shortest adult lifespan of any animal, at just five minutes?

Emails are the sales and marketing equivalent of those short-lived mayflies. Research shows that if they’re not opened on the day they’re sent, chances are they never will be.

So it’s astonishing to learn that 70% of unanswered sales email chains stop after just one email.

To help you change all that, in this article I’m going to give you a bunch of high-quality follow-up email subject line examples you can use to level up your email outreach campaigns.

Best Practices For Follow-Up Email Subject Lines

Give someone a follow-up email subject line and they’ll be able to send one perfect email. Follow-up emails are mandatory to get responses from your precious. Without following a proper guide people do tons of mistakes sending out their follow-up emails.

Give them the knowledge to craft their own subject lines and they’ll have (some of) the tools to run successful cold email campaigns for life.

That’s why I’m starting this article with my top 10 best practices for improving your follow-up subject lines.

#1. Begin with a Question

Questions are a powerful cold sales email tool because they pique the recipient’s interest and compel them to open the email. And the more opens you generate, the higher your response rate will be.

Not only does this tactic stimulate curiosity, but it also makes you sound conversational rather than pushy, which helps you get off on the right foot with your prospect.

#2. Personalize Using Names

Adding personalized subject lines makes it 26% more likely your emails will be opened. That “personal touch” could involve mentioning the prospect by name, referencing their company name, or even highlighting a shared experience — maybe you both attended a recent conference or attended the same school

#3. Identify Yourself

Obviously, you’ll have explained who you are and what you do in your introductory email. But that email didn’t receive a response, and may not have been opened. So it might make sense to spell out exactly who is sending this email. At the very least, it’ll put a name to your emails, which is the first step toward building a relationship with your prospect.

#4. Praise your Prospects

We all love a bit of flattery. If you send me an email with a subject line that says how much you love my blog posts, and it actually appears authentic, I’ll probably open it! Of course, it needs to be a meaningful compliment (i.e. don’t tell someone how funny they are on Twitter if they haven’t tweeted since 2009), and you need to reference it in the email body copy — otherwise, it just looks fake.

#5. Don’t Be Afraid To Add Humor

Let’s be honest: most sales and promotional emails are boring. So a genuinely funny email subject line will definitely stand out in your prospect’s busy inbox.

Writing funny emails is easier said than done, though. And be aware that you might not have the same sense of humor as your prospect, in which case they might not appreciate (or understand) your hilarious quip.

#6. Provide Relevant Value

Every cold sales email wants something from the prospect (attention, time, money). But not many offer to give anything back. That’s why adding value — such as promising to solve a pain point or share a useful tool — can make for an effective follow-up email subject line. Just make sure the value you offer to provide is actually relevant to your prospect’s needs.

#7. Be Brief And Non-Descriptive

When it comes to writing an impactful sales email subject line, brevity is your friend. Research from Marketo found that four-word subject lines see the highest open rates, which doesn’t give you much scope for creativity.

Fortunately, if you’re looking to keep things as brief as possible, non-descriptive subject lines can often spark curiosity from recipients — so don’t worry about coming across a little vague. It might even play in your favor.

#8. Optimize Subject Lines For All Devices

Okay, so we already know shorter email subject lines tend to perform better. But remember, subject lines display differently from one device to another:

Desktop inboxes show around 60 characters
iPhone inbox (in portrait mode) shows 41 characters
Android inbox (in portrait mode) shows 30 characters

In other words, if you can craft an impactful subject line in 30 characters or fewer, do it, because it’ll display in full across all devices.

#9. Create Urgency and FOMO

If you can give your prospect the impression that they’ll miss out on something amazing and highly valuable if they don’t read your email is a fantastic way to boost your open rate.

Once again, just be sure to back up the “promise” of your subject line in the email message itself. Otherwise, you’ll get a ton of extra opens but no more replies.

#10. Name Drop Mutual Friends

Dropping the name of a shared connection can definitely earn you some extra kudos, particularly if that shared connection would be happy to vouch for you.

But only mention a mutual contact if it’s relevant. The fact that you both follow GaryVee on LinkedIn probably doesn’t count.

Follow-Up Email Subject Lines from Successful Campaigns

Enough theory. Now let’s get into the good stuff.

Without further ado, here are 20+ killer follow-up email subject lines to spark your prospects’ interest, compel them to open, and encourage them to hit “reply”.

1. Follow Up Email Subject Line For Sales Outreach

The same research I referenced in the introduction to this article reveals another interesting point about sales pitch emails: the more emails you send, the more chances there are for prospects to respond.

Sounds obvious, right?

But it definitely hammers home the importance of a quality sales email subject line. Something that captures the recipient’s attention.

There are lots of ways you could do that, but these subject line examples leverage the powers of personalization and the promise of added value:

{{contact_company||your company}} <> Postaga?
For {{contact_company||your company}}?
SEO Agency Advice
Question?
Quick question?

2. Follow Up Email Subject Line After a Meeting

To be clear, this isn’t about following up after an internal meeting. It’s about reaching out to a prospect you met at a business or networking meeting of some description. Sending a killer follow-up email a day or two after the event helps to lay the groundwork for a meaningful relationship.

Key takeaways from meeting on {{meeting theme}}
Thanks for attending our meeting on {{date}}
Following up – {{company name}}

3. Follow Up Email Subject Line For After a Presentation

You’ve just given a presentation. Naturally, you want to ensure that you didn’t miss anything important. And you also want to check that the attendees remember all those fascinating points you made. So, naturally, you send a followup email with a subject line like:

Did I miss anything?
Key takeaways from presentation on {{date}}
X key points from {{presentation title}}

4. Follow Up Email Subject Line For Guest Post Outreach

Looking for guest posting opportunities is one of the most popular reasons for sending outreach emails. These emails need to attract your prospect’s attention and start building a guest posting relationship that benefits both parties. In my experience, your best bet here is to write a subject line that’s totally transparent — don’t hide the fact that this is about guest posting deep in the email body.

A good subject line also separates you from the dear sir link sellers.

Guest Post – Content collab with {{contact_company||your company}}?
Guest Post – Do you accept quality 1000+ word guest posts?
Guest Post – Hey {{contact_first||there}} // Content Opportunities – Andy from Postaga
Guest Post – Hey {{contact_first||there}} circling back for awesome 🤘 collab
Up for a content collaboration?

5. Follow Up Email Subject Line For Skyscraper Outreach

Similar to guest posting, skyscraper outreach works best when you’re upfront about your intentions: your prospect has linked to a competitor’s blog, and you want them to link to your blog instead. Both parties know what’s going on here, so don’t be afraid to add a little humor to your subject line.

Skyscraper – Reinserting attention-grabbing email subject line here
Skyscraper – Your superb 🤩 post on {{link_title||your post}}
Skyscraper – You got good blog, I got good blog, let’s do this 😉
Skyscraper – Your post on {{link_title||your post}}
Skyscraper – {{contact_company||your company}} <> Postaga
A suggestion for your article on {{subject}}

6. Follow Up Email Subject Line For Link Building Outreach

Pages with lots of backlinks outrank pages with fewer backlinks. In fact, Backlinko discovered that the #1 result in Google has, on average, almost four times more backlinks than positions #2 – #10. So it pays to be good at link-building outreach. And part of the puzzle lies in crafting impactful follow-up subject lines, like:

Interested in content on {{topic}}?
I wrote this blog on {{topic}} and I’d love you to see it!
We wrote something you’ll love
Did you know: {{Pull out key stat from your content}}

7. Follow Up Email Subject Line For Link Exchange Opportunities

Links are valuable, so it makes sense to “swap” backlinks with other sites, right? I’ll scratch your back if you scratch mine. But exchanging links is a violation of Google’s guidelines, so some SEOs attempt to get around it through ABC link exchanging: Site A links to Site B; Site B links to Site C; Site C links to Site A.

If you’re going to use this link-building tactic, give these subject lines a whirl:

SEO collaboration: {{contact_company||your company}} <> Postaga
Interested in link-building opportunities?
Hey {{contact_first||there}} // Link-Building Opportunities – Andy from Postaga

8. Follow Up Email Subject Line For Digital PR

The average reporter responds to just 3.49% of digital PR pitches they receive. When your email recipient is busy (which journalists invariably are), you need to get used to sending a polite follow-up email or two. And, clearly, your subject lines will make a big difference.

Article on {{topic}} with the latest statistics 🤓
Did you know: {{Pull out most interesting stat or angle from your press release}}
Hey {{first_name}}, I love your writing!

9. Follow Up Email Subject Line For Non-responsive Influencers

Influencers are similar to journalists in that they’re both time-poor. Unlike most journalists, a lot of (smaller) influencers are one-person teams, so it’s hardly surprising they don’t respond to every email they receive. Boost your chances by trying these subject lines for size:

Hey {{first_name}}, Postaga loves your content! ❤️
Collab: {{first_name}} <> Postaga?
Are you open to collaborations?

10. Follow Up Email Subject Line For Podcast Outreach

Want to get interviewed on a podcast? It’s all about finding the right podcast, then reaching out and explaining your unique expertise — something they couldn’t get without you.

Pro tip: Postaga can help with this.

Depending on the popularity of your chosen podcast(s), they might get a ton of these emails, so a snappy subject line is crucial.

Podcast Guest?
We just raised X amount on TinySeed! 💰
I love your episode on {{topic}}!

11. Follow Up Email Subject Line For Mention Outreach

Mention outreach is a simple technique that involves reaching out to sites you’ve linked to and asking them to share your content via social media. That way, you get to tap into a much larger audience. But as with any email outreach campaign, it won’t work without a compelling subject line.

Unlinked Mention – Ooh Ooh! Had another question
Mentioned {{contact_company||your company}} in a recent post
Mention – Hey {{contact_first}}, {{link_title||your post}}
Unlinked Mention – Quick Question?

12. Follow Up Email Subject Line For Reviews Outreach

You’ve found a site that reviewed your biggest competitor’s product. So why not ask them to take a look at yours, too? That’s reviews outreach in a nutshell! Again, it pays to be upfront in your subject line — don’t make the recipient guess the reason for your email.

Reviewing {{Your_Company_name}}?
Your {{competitor}} Review
An article idea related to one you wrote on {{company}}

13. Follow Up Email Subject Line For Product Promotion Outreach

You’ve got a great product, but wouldn’t it be great if more people knew about it? Sounds like it’s time for a spot of product promotion outreach. It’s all about connecting with publishers whose audiences would be interested in your product, (briefly) describing the key features, benefits, and problems it solves, and compelling them to find out more.

Product Promotion Tools – Your {{keyword}} tools post
Have you checked it out yet? 👉👈
Product Promotion Tools – Had another question about {{keyword}} tools
Your article on {{keyword}} tools

14. Follow Up Email Subject Line For Expert Round-Up Outreach

With roundup outreach, you search for relevant blogs that publish roundup-style articles sharing content from multiple other sources covering a specific topic or industry. Naturally, they could be sharing your content in their next roundup (or in a previous one).

Expert Campaign – Weighing in on {{keyword}}
Round-Up – For Your Next Roundup Post?

15. Follow Up Email Subject Line For Resource Campaign Outreach

Kind of like roundup outreach, resource outreach is about finding blogs that share their favorite resources on a given topic. Obviously, that topic should be relevant to your brand and product. That way, asking them to include you in their resource should feel pretty natural.

Resource Campaign: Your {{keyword}} resources
{{Product name}} would be a great fit for your post on {{keyword}} resources
Have you heard about {{product name}}?

16. Follow Up Email Subject Line For Non-Responsive Collaboration

I get it: you’ve found an amazing, mutually beneficial collaboration opportunity, but you haven’t received a response from your initial email. It’s frustrating.

But you might have caught them at a bad time. Maybe they just didn’t get chance to read your original message. So try following up with one of these subject lines:

Collab with {{contact_company||your company}}?
ICYMI: Are you open to collaborations?
Collaborate with an expert on {{topic area}}

17. Follow Up Email Subject Line After An Event

Regardless of your goal, speaking to someone at an event gives you a distinct advantage when it comes to building a business relationship, because you’re not just another random name in the prospect’s inbox. You’re a real person, with a face and everything! But that still doesn’t guarantee you a response, so a strong follow-up game is essential. Use these examples as inspiration for your next networking follow-up email subject line:

Hey {{first_name}}, remember me?
Remember speaking at {{event name}}?
It was great meeting you at {{event name}}!

18. Follow Up Email Subject Line After a Mutual Connection

Having a mutual connection can give you a big advantage in your quest to strike up an ongoing relationship with your prospect. So it makes sense to leverage that person’s name in your subject line. Just make sure you explain your connection with them early on in the body copy, otherwise it looks kind of weird.

Do you know {{mutual connection’s name}}?
{{Mutual connection}} suggested I reach out to you

19. Follow Up Email Subject Line For Affiliate Partnerships

Great affiliates — those that send consistent, warm leads and sales in your direction — are extremely hard to come by (but Postaga can make it easier).

That’s why a lot of brands take the time to bolster their line-up of affiliates by reaching out to potential publishing partners. But once again, the best affiliate marketers are busy, and they receive a ton of offers, so your emails need to cut through the noise.

Affiliate – Affiliate partnership?
Affiliate – What about Us?
Affiliate partnership: {{affiliate_website_name}} X {{Your_Company_name}}?

20. Follow Up Email Subject Line for Virtual Summit Outreach

Think webinars are a flash in the pan that will gradually fade away in a post-pandemic world? Think again! According to LinkedIn, 45% of future business events will be virtual. But if you’re going to make the most of virtual events, you need to attract the right people — and often, that means getting proactive and doing a little outreach.

Virtual Summit Outreach: Invite to lead generation summit for {{contact_company||your company}}
Date for your diary: {{Event_Date}}{{Event_Title}}
Want to learn about {{event theme}}?

Why You Should Not Add A New Subject Line

All of this being said, you might not want to use a new subject line on your follow-up email.

Why?

The short answer is that if your follow-up email has a different subject line as your previous emails, the previous emails might not show up in your email thread and your recipient will have no idea what you’re reaching out about, because the recipient’s email inbox will treat it as a brand new email unrelated to your first email.

The longer answer: Threading is handled on the recipient’s email server end. As the sender, you cannot tell their email software whether or not to thread an email and combine your new email with your previous emails in a conversation. Normally, email servers will thread an email if the subject line is the same. When you see “Re:” in the subject line, that’s actually not from the sender, but your own email client. Your email client sees that the subject is the same, and they thread it and add the Re: for your convenience. If you change a subject line, there is basically 0 chance it will end up threading. So, you should never have a follow-up email with a different subject line unless you don’t care if it’s threaded with the previous emails.

Is there a way to keep the email thread with a new subject line? No. Like I mentioned, it’s all handled by the recipient email server. You can’t control that as the sender. And from what I understand, there’s not a way to make the recipient email server thread emails with different subject lines. If anything, different subject lines tell the recipient that these are unrelated messages.

You could conceivably send an email that includes the previous email contents below it, which we have considered, but that would technically all be in the same email, not a threaded email with the older emails below it

So why do people still add new subject lines in follow-up emails?

Because they don’t care that the email isn’t threaded. They care about getting the recipient to reply. They might be thinking, “OK, so they didn’t open or respond to my first email. Let me try a different subject line and approach, rather than just see “Re: the same subject line that didn’t get me to open the first email”.

To Wrap It All Up

No one wants to send follow-up emails. They make you feel pushy.

But the average person currently receives almost 320 emails a day, and that number is only going to increase.

With all that noise, it’s inevitable that a lot of your initial emails are going to be missed or ignored. Want superior mastery over your follow-up emails read out in-depth guide on follow-up emails.

So if you’re not sending high-quality follow-up emails with eye-catching, must-click subject lines, you’re definitely missing out on a ton of leads and sales. You’ve conquered how to write the follow-up subject line. Not sure how to write the perfect follow-up email? give this a read.