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Better subject lines 🏁 faster (12 slick tips)

good subject lines

New here? This is Inbox Hacking, a Free Newsletter for Awesome email marketers eager to level up. Email marketing insights, tools, & tactics sent twice per week. Someone forwarded you our Newsletter? Please join over 14,728 Email Marketers and sign up for your Free subscription. Today’s edition→ 12 tips for better subject lines done faster (+ 33 examples).

Got those taxes filled out? Good, me neither.

Who has the time! Well, after today’s feature story, you’ll finally bank some free time. I’ve got 12 tips for improving your subject lines and writing them more efficiently. Some, you don’t have to write at all.

Copy Paste Proven Subject Lines

Subject lines (SL) either get your email opened or ignored. So you wanna write the best ones you can – but without wasting time.

🔑These subject lines are not someone’s guesses at what could work. These were tested via cold emails:


  1. “5 things you didn’t know about [Topic relevant to prospect]”
  2. “Why [Company]? And why now?” (a double question🔥)
  3. “Better subject lines 🏁 faster (12 slick tips)” {sound familiar?}

What about proven triggered email examples? 

  • “⚠One item in your cart is about to sell out” (edited from this list)
  • “Explore your billing and payment options” 94.7% open rate (Welcome email) vs. “Account and billing options you need to know” 85.3% open rate

Subject lines that appeal to human nature:

  • “This week’s reviews for Sydney!” (leave out exclamation marks→ overused)
  • “What your neighbor’s doing this weekend🤫” (gossip – effective since language began)

Wait. Do the results of the SL test below go against human nature?

A) “You’ll get [result they want] with this [tactic used]”

B) “I got [result they want] with this [tactic used]”

Freelance AI Help

Using proven subject line guidelines like those above, you can also get the newest version of ChatGPT to assist you. (*GPT-4 requires $20/month subscription)

But even the sharpest AI writer might waste your time unless you know the best ways to prompt the bot.

Here you go:

Plus, you can speed up writing your preview text by prompting GPT-4 to rephrase your subject line, extend it, insert synonyms, summarize it, etc.

Too busy to even try AI?

Subject Lines Done and Tested for You

good subject lines

Feel free to use the best of these 20 subject lines I created with the free version of ChatGPT. I then tested them with two different SL testers. 

You’re welcome. Actually, thanks… testing helped me procrastinate on taxes more. 

Prompt used: “Please write 20 different subject lines that use urgency, personalization, one emoji, and curiosity.”

Checked with Sendcheckit (point range 0-109)

🚨 Don’t Miss Out! Our Limited Time Offer Ends Soon. (score 89)

📢 Attention [Name]: Important Update Inside (score 93)

⏰ Hurry! Last Chance To Claim Your Exclusive Discount (score 77)

🚀 Time-Sensitive: Our Biggest Sale Of The Year Is Here! (score 80)

🎁 [Name], Here’s A Special Gift Just For You! (score 94)

💥 Limited Stock Alert: Get [Product] Before It’s Gone (score 87)

🛑 Urgent: Your Account Requires Immediate Action (score 83)

🤔 Have You Heard? [Big News] Just Announced! (score 94)

🌟 Vip Exclusive: Be The First To Get [New Product] (score 89)

🔥 Hot Off The Press: Breaking News You Need To Know (score 104)—ALT version scored 109 “🔥 hot off the press: need-to-know breaking news”

Below checked with Omnisend (point range 0-100)

🤑 Act Fast! Don’t Miss Out On Our Money-Saving Deal (score 67)

💡 [Name], We Have An Idea You’ll Love (score 83)

🚨 Emergency Alert: [Important Information] (score 57)

🎯 You’re Invited: Join Our Exclusive [Event] (score 83)

💻 [Name], We Have A Tech Update You Need To See (score 75)

📈 Time To Upgrade: Our Newest [Product] Is Here (score 50)

🤫 Shh… [Name], This Exclusive Offer Is Just For You (score 42)

💰 Save Big With Our Limited-Time Offer (score 75)

🚨 Urgent Reminder: Your [Deadline] Is Approaching (score 67)

🎉 Celebrate With Us! You Won [Prize]! (Score 50)

Note: The bot capitalized each word, which is not typically suggested. Also, I inserted usable words in the brackets for the tests.

Hey, you may not like ChatGPT at all. Luckily, it’s not the only game in town.

SubjectGeni produces subject lines as well as complete emails, SMS, and multi-touch campaigns. See screen grab below to learn how it justifies subject lines it spits out.

good subject lines

More stats and facts below + today’s asap email hack.

Knowledge Base

🔥Knowledge is power, but first, lean back for a sec.

Plan to be in business the next 7 years? Use this evergreen content tutorial.

👀Eye-popping visuals can rekindle your newsletter (examples).

Amp up subject lines (10 ways & #6 is a must-use).

🌹(Sunday, May 14th) Mother’s Day marketing ideas done for you.


EMAIL MARKETING: How to resuscitate your “dead” email subscribers and bring them back into the purchase funnel. Inbox Mailers ignites re-engagement. They leverage a unique engagement trigger system that we’ve seen double, even triple open rates. Traders Agency used these triggers, which resulted in 3x conversions.

🆓Book My Demo

Self Help 

I don’t expect you to quit your job to start surfing or growing hemp full-time after watching this How-to on Easy Living.

But if it inspires you to be 7% more carefree or avoid hustle-heroics a few more weekends per year, then my work here’s done. *Grabs kayak paddle🛶*

*Shout-out to Inbox Hacking Subscribers → 

🌎David at MapPost (Travel)

📈Guy at Mavericks Unlimited (Growth)

🏃🏼‍♀️Gene at Charity Miles (Miles=$)

Facts and Stats

  • Consumer survey: 38.3% are comfortable with brands using personal data like name, age, location, for a better experience / 10.1% not comfortable (Moengage)
  • Month for highest click rate and click-to-open rate→ June (GetResponse)
  • Industries using double opt-ins least— 1. Real estate 2. Legal services 3. Tech

From Our Sponsor

If you use email marketing for your business, you’re gonna want to check out Inbox Mailers.

They’re changing the game.

Their software enables brands to know when subscribers are in their inbox while triggering an email that generates a 50% – 70% open rate→ with no decline in click-to-open rates💥.

The best part? 

Inbox Mailers integrates with almost all major ESPs to easily and instantly fire your triggered email, using your ESP, from your domain at the time your subscriber is in their inbox.

🆓Book My Demo

Marketing Musings

Don’t feel bad when your conversions are not as high as you hoped.

You’re in the same boat as most.

Don’t believe it?

Browse Pinterest and witness all the things people are NOT actually doing. 

They hope to though, and one day might. So keep emailing, for those who one day will convert.

Get Hacking

Visuals in emails make a splash. 

Using 26 plain characters can too.

Here’s inspiration for both.

good subject lines

good subject lines

Most mailers can’t replicate Huckberry’s photos. But can you enhance your visuals by 10%? Hint: yes. 

BrainFood uses a writing formula that can be replicated with practice.

Use whichever method fits your campaigns to make them 10% better. Start asap.

*Know another brilliant email marketer? Please forward this newsletter to them (thanks for reading).

🎈Please take survey below. Benefits residents of Okay, Oklahoma battling average problems.