17 Best Cold Email Subject Lines for Higher Open Rates

Cold email outreach is a tough game. It can chew you up and spit you into the spam folder before you’ve even had the chance to sip your morning coffee.

Sending cold emails has a bad reputation because most people suck at it. The worst thing you can do to a prospect is send them a stale subject line that's uninspired and clearly copied + pasted.

Adding a prospect's name or company did the job 10 years ago. It worked back then because it was new. Now everyone is doing it, so it’s clearly a cold email. Today, people expect more—dig deeper, tap into their goals, and offer opportunities that are too good to pass up. 

In line with this, our AI Email Writer tool can be a game-changer. It not only helps in crafting engaging subject lines but also assists in generating personalized email content that resonates with your prospects' current needs and goals. This way, you can add a personal touch to each email and improve your chances of getting a response. Try our AI Email Writer tool to elevate your cold email game: AI Email Writer Tool.

Show your prospects that you care. Take a look at what moves their company is making, dig into the challenges facing their role today, and think about what they’re trying to achieve right now. 

Here are our current favorite cold email subject lines that’ll get your outreach emails opened.

1. Idea for your [pain point]

Why it works: It's quick and to the point. This subject line focuses on delivering value to your prospect in the form of an idea that ladders up to a broad goal they’re reaching for. You can also use it for a variety of cold outreach emails for similar prospects in the same industry without having to personalize each one (time-saver alert! 🚨) 


  • Idea for your eCommerce store
  • I have an idea to grow your traffic

2. New tool for [type of role/problem]

Why it works: Connect with a cold lead immediately by mentioning their job role or a problem they face. Personalizing a subject line with a minor tweak like this can help your email get noticed in a prospect's inbox. Plus, keeping it short indicates there’s a good chance your email is short, too. 


  • New tool for busy marketers
  • New tool for getting more leads

3. My plan for [goal]

Why it works: Every prospect has goals or targets they need to hit in their job role. For example, marketing and operations leaders in SaaS companies are often concerned with ways to reduce churn. Pick a high-level goal for your cold lead and make it clear you can help them reach it. The little touch of adding “My” to the beginning of your subject line can establish a more immediate personal connection—just be sure your email (quickly) delivers on a preview of your plan.


  • My plan for reducing your churn
  • Planning your next feature update

Want to get a head start with cold email subject lines? Take our (free!) subject line generator for a test drive.
Subject Line Generator

4. Cut [reduction goal] by [measurable result]

Why it works: Numbers always capture attention in a subject line, just make sure you can back them up. If you can prove you’ve helped others in their industry hit a particular reduction goal for a key business metric, they’ll sit up and listen.


  • Cut engineering costs by 45% 
  • Reduce your abandonment rate by 20%

5. Grow [goal] by [measurable result]

Why it works: This subject line is the inverse of #4. In the case of revenue, customer growth, and many other core business metrics, the goal isn’t to reduce numbers, but to increase them. Grab your prospect’s attention by including measurable results wherever possible. 


  • Grow organic traffic by 45% 
  • Double sales rep productivity 

A final tip for these number-based headlines — don’t get outlandish. No one is going to open an email that promises “Increase your revenue by 400% in 2 days!!!” That will land you in the spam folder faster than you can say “low open rates.” 

6. [Your company name] + [prospect’s company] = [goal]

Why it works: This catchy subject line paints your company as a partner. Instead of trying to just sell the potential prospect something, it says you want to work with them. 


  • Close + Shopify = more deals
  • Lakeside Accounting + Joe’s Tire Shop = lower taxes 

A variation of this subject line was tested out on us by a company called Brex. Here's how they reached out 👇 

What I love about this type of cold outreach is the sales rep kept the internal email trail when they first reached out. It wasn't a mistake. It's so we could see they were discussing how we would be a good fit. It shows Close isn't just some random cold lead target and they really thought about us. 

Screenshot Example of the FWD Manager Cold Email Template

It's bold. But sometimes gambles like this payoff. 

7. I’ll help you [achieve goal]

Why it works: This one helps prospects see you are a real person—not a corporation. By changing the usual "we" to "I", it can get them thinking about a 1-on-1 partnership. 


  • I’ll help you scale up your blog content
  • New strategy to get more customers in [prospect’s city] 

Take it from me: if a cold email lands in my inbox and mentions someone I know… I pay attention. 

Tap into your existing network, whether on Twitter, LinkedIn, or your customer base, to see if a cold lead has any mutual contacts. If they do and the mutual contact okays the referral, go ahead and reach out with these subject lines. 

8. [Mutual contact] gave me your info 

Why it works: Even the busiest prospects recognize a friend or colleague's name in a subject line. Use this to your advantage to give your email the best chance of getting noticed, just make sure you’re not using this as a ploy to boost open rates without a genuine connection.


  • John Smith gave me your info
  • Claire from Etsy told me to ping you 

9. Fellow [personalization]

Why it works: People get totally nostalgic (and intrigued) about things like old university stomping grounds and hometowns. Capitalize on that with a subject line that gives juuuust enough away to get your email opened.  


  • Fellow FSU alum
  • From a fellow VP of sales
  • Hey, fellow Jacksonville local!

10. [mutual contact] loves us

Why it works: Okay, this one is a bit cheeky. It combines a mutual prospect and social proof right off the bat to make an intro. It's straightforward—but you might be surprised how well this approach works! 


  • Ryan at Close loves us
  • Ferris Bueller at Intuit says hey
  • Gob Bluth digs Asana, we think you will too 😉

11. 15 minutes to [action related to relevant goal]

Why it works: People are busy. Reassure prospects that you don't need a lot of their time to help them reach a goal. 


  • 15 minutes to reduce your email marketing spend
  • 15 minutes to improve your Instagram reach

12. FOMO is worst [optional pain point mention]

Why it works: There’s nothing like a sense of urgency, right? Instead of going the “Don’t miss out!” route, this subject line mentions FOMO right off the bat to get a prospect's attention. It’s fun and a little quirky, but it might help you stand out. 


  • FOMO is the worst
  • FOMO sucks, don’t miss out on more leads

13. Hit [important metric] before [time period]

Why it works: If you know your ICP well enough, you have a good idea about what goals they need to hit in their job role. So, use this knowledge. Social media managers want more followers and views, while startup founders need to hit revenue targets. Put a specific metric in your subject line to get your email opened. 


  • Get 10k X (Twitter) followers before EOY
  • Hit $30k in MRR before the end of Q4 

14. Frustrated with [pain point]?

Why it works: The most successful emails make potential customers sit up in their chair and think, "Shit, this person can actually help me!". Tap into that mindset and highlight a problem/topical issue they could struggle with. 


  • Frustrated with Google SERP results?  
  • Pissed about your traffic? 
  • How are you handling lead quality?
  • Want to eliminate bill pay stress? 

15. The problem with [product] 

Why it works: Sites like Wappalyzer identify what products a lead uses by trawling their website. If a competitor pops up on the list, target its weaknesses and show a prospect how your company is a more valuable solution. 


  • The problem with Webflow
  • Biggest flaw in Salesforce

16. [Related business] just [achieved goal] with us

Why it works: Results matter. Brag about the success similar customers in the prospect's industry have had with your product and show you can get the job done. 


  • Calendly just increased close rates by 3X with us 
  • Mike’s Tires just doubled walk-ins with us

17. Quick collab idea [optional personalization]

Why it works: Partnerships can be a business' bread and butter. Offer to team up with a prospect and work with them on a project that has mutual benefits. If it fits your brand, you can even drop an emoji. 


  • Quick collab idea for Close 🤝
  • Quick collab idea to increase sales 

Pro tip: You can automate personalization like names, competitor names, and job roles, and still be authentic. Close uses Custom Fields to save details like these in a contact's information. Then, our tool will dynamically include them in different subject lines:
Email Subject Lines - Use Custom Fields at Close

6 Tips to Craft High-Performing Cold Email Subject Lines

Even if a cold subject line has the right ingredients, there are still some tactics that can increase the chances of connecting with a prospect. 

Here are the boxes you should check on your subject lines before you hit send 👇

1. Keep it Short

Your prospects are busy. 

Always remember this when writing a subject line and keep it as short and engaging as possible. The reason for this is two-fold: 

✔️ Short subject lines force you to be clear and concise in your messaging. By cutting the fluff, your message will be more focused and immediately get the point across to the prospect. 

✔️ A ton of prospects check email using a mobile device. A good subject line will display in full when they open their inbox. 

Remember, less is more. And for your future follow-up emails, brevity is even more crucial.

2. Be Ultra-Relevant

Here's the harsh truth: you are just one of many sales reps trying to reach a prospect and sell them something. 

Make every subject line you write ultra-relevant to the person you are emailing. We've already talked about a bunch of ways to do this, like highlighting mutual connections, discussing a prospect's goals, and even checking out any competitors they currently use to see if they're a good fit. 

Whatever it is, make sure personalization goes beyond just inserting {FIRST NAME} and {COMPANY}. If you’re on the fence about using emojis, check your subject line real estate and make sure you’re not bogging them down at the expense of trying to be too creative.

3. Sprinkle in a Bit of FOMO

Motivate prospects to reply by appealing to their fear of missing out (FOMO).

How you target this FOMO will depend on your prospect. For example, a startup founder will itch at the thought of a competitor getting ahead of them on Q4 revenue, so offer them a way to increase earnings using your product. While this subject line wouldn't necessarily interest a marketing manager, a (limited entry) masterclass to a social media event just might. 

Here are a couple of FOMO examples for you to steal: 

  • Limited-time offers. A simple "24 hours until we end this deal" is a last-minute (but often successful) trick to get an email opened.
  • Scarcity of available seats. Use something like "Only four seats left in our social media masterclass!" to get them thinking. 
  • Social proof. Prospects are usually curious about how you help others before they sign up themselves. Leverage this with subject lines like "Over 2,000 successful founders can't be wrong!" or "We helped [similar company] triple their revenue"

4. Avoid Clickbait

Nobody likes opening up an email that doesn't deliver on a promise. 

Don't get me wrong—clickbait-y subject lines will get an email opened. But it's also the fastest way to kill a relationship with a prospect and erode trust in your brand. Before you send out a cold email, ask yourself: 

  • Does the subject line promise (or allude) to something that the email itself doesn't have?
  • Does it set unrealistic expectations of what's inside the email? If your subject line reads "The most helpful content you will ever receive!" and it's actually a link to a recorded webinar… they will probably be disappointed. 

If the answer is yes to either—take the email subject line back to the drawing board. 

5. Work on Email Deliverability

Writing the best subject lines is just part of the strategy. Making sure it reaches your prospect's inbox is the next hurdle.

A lot of this comes down to email deliverability. This is how trustworthy your email address is along with other factors like if you send out emails a prospect actually wants to receive. You can improve email deliverability if you: 

  • Focus on sender reputation. This is how Internet Service Providers (ISPs) decide how trustworthy you are. Always use a reputable email service provider when sending out cold emails and avoid being marked as spam by potential prospects, as this will land you in hot water with ISPs. Steer clear of clickbait language and if a prospect unsubscribes from an email list or says they aren't interested—don't keep messaging them!
  • Clean up your email database. Do a regular check of your email list. Remove anyone who doesn't open your messages or has given an invalid email address when downloading lead magnets like case studies. This will lower bounce rates and improve your sender reputation. 

Also, watch for any spammy words or punctuation in your subject line. Excessive text formatting, punctuation, and "curse words" like $$$ or You have been selected are the quickest way to get flagged in spam filters. 

6. Use Your CRM to Track Conversations

Lastly, track which subject lines work (and which ones don't) using your CRM.

A CRM can monitor every email interaction you have with a potential lead and store important details that will push a deal forward. For example, if a cold lead says they have just started a contract with a competitor but asks you to check back with them in 12 months, you can create a reminder in your CRM to do just that. 

CRMs are also perfect for monitoring cold email campaign performance to see which subject lines were best received, along with other metrics like open rates and response rates. This data is super helpful to help tweak cold email subject lines and include language that resonates with your target audience. 

Close makes all this work around cold email subject lines easy. Thanks to tools like email workflows, detailed lead data, and our subject line generator, you can send better cold outreach campaigns and get more prospects in your sales funnel 💰

Looking for a quick and easy way to create personalized cold email subject lines? Check out our (free!) subject line generator!

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