Email Marketing Guide
50+ Email Subject Line Examples That Get Opens
Your subject line is the first — and sometimes only — thing subscribers see. Get 50+ proven examples across every email type, plus the formulas and tips to write your own.
1. What Makes a Good Email Subject Line?
Think of your subject line as a 50-character headline on a newspaper stand. It has one job: get the person to open the email. A great subject line does at least one of the following things:
Sparks Curiosity
Opens a loop in the reader's mind that can only be closed by reading the email. e.g. "You're making this mistake every Monday"
Promises a Benefit
Tells the reader exactly what they'll get from opening. e.g. "5 templates to write faster emails"
Creates Urgency
Adds a reason to open now rather than later. e.g. "Sale ends tonight — last chance"
Feels Personal
Uses the subscriber's name or references something relevant to them. e.g. "Priya, your cart is waiting"
Length tip
Keep subject lines between 40–60 characters (6–10 words). Most mobile apps truncate at around 40 characters, so front-load your hook. Preheader text (the preview line) adds another 80–100 characters — use it to complete the thought.
New to email marketing? Read our Email Marketing for Beginners guide for a full foundation before diving into subject lines.
2. Subject Line Formulas That Work
These are the frameworks used by professional email marketers. Each formula has a different psychological trigger. Mix and match them depending on the email type.
Number + Benefit
Sets clear expectations. Readers know exactly what they're getting.
How to [Achieve Outcome]
Classic tutorial hook. Works well for beginners who want instruction.
Question
Forces the reader to mentally answer, creating engagement before they even open.
Urgency / Scarcity
Works well for promotions and time-sensitive content. Don't overuse — it loses impact fast.
The [Unexpected Angle]
Contrarian or surprising statements that interrupt pattern recognition in a crowded inbox.
Personalisation
Using the subscriber's first name or behaviour lifts open rates by 20–26% on average. Easy to set up in MailerLite, Moosend, or ActiveCampaign with merge tags.
3. Welcome Email Subject Lines
Welcome emails have the highest open rates of any email type — often 50–80%. That means your subject line just needs to be warm, clear, and on-brand. Don't overthink it here; the relationship matters more than the hook.
For full welcome sequence templates, see our Email Welcome Series Examples guide.
Welcome Subject Line Examples
Tip: Welcome emails sent immediately after sign-up get 3x higher open rates than those sent a day later. Use your email platform's automation trigger to send instantly. MailerLite and Moosend both make this simple to set up with no coding required.
5. Ecommerce Subject Lines
Ecommerce subject lines cover the full customer lifecycle — from browse abandonment to post-purchase follow-up. The most important rule: make the benefit or product the star, not generic promotional language.
Abandoned Cart
Post-Purchase
Browse Abandonment
Replenishment
6. Promotional Email Subject Lines
Promotional emails compete in the most crowded part of any inbox. The secret is specificity — tell subscribers exactly what the deal is, and how long they have. Vague urgency doesn't work; specific urgency does.
Promotional Subject Line Examples
Watch out: Using ALL CAPS, excessive exclamation marks (!!!), or spam trigger words like "FREE MONEY" or "Act NOW!!!" can send your email straight to spam. Use urgency through specificity, not through shouting.
7. Re-engagement Subject Lines
When subscribers go quiet — no opens for 60–90 days — it's time for a re-engagement campaign. The goal is simple: get one more open, or confirm they want to unsubscribe so your list stays healthy.
Re-engagement emails are a key part of a broader automation strategy. See our Email Marketing Automation Examples for the full workflow.
Re-engagement Subject Line Examples
Tip: Honesty works well in re-engagement emails. Subject lines like "Should we say goodbye?" or "Are you still there?" outperform over-enthusiastic ones because they're unexpected and human.
Put These Subject Lines to Work
You need a platform that makes it easy to A/B test subject lines, personalise with merge tags, and automate your sends. Here are two we recommend for different needs.
MailerLite
Best for beginners & newsletters
MailerLite has one of the cleanest subject line A/B testing interfaces on the market. You can test two subject lines with a single click and let the winner send automatically. Generous free plan up to 1,000 subscribers.
- Built-in A/B subject line testing
- Personalisation merge tags
- Free plan — no credit card needed
Free up to 1,000 subscribers · Affiliate link
Moosend
Best for automation & ecommerce
Moosend's automation builder is ideal for triggering emails based on subscriber behaviour — making it easy to send cart abandonment, re-engagement, and post-purchase emails with the right subject lines at the right time.
- Advanced behavioural triggers
- Affordable — starts from $9/mo
- 30-day free trial
30-day free trial · Affiliate link
We may earn a commission if you sign up via these links — at no extra cost to you. We only recommend tools we genuinely endorse.
8. Common Subject Line Mistakes to Avoid
Even experienced marketers make these errors. Avoiding them can improve your open rates without changing anything else.
Being too vague
"Check this out" or "You'll love this" tells the reader nothing. Specific subject lines always outperform vague ones. Tell them what's inside.
Writing too long
Subject lines over 70 characters get cut off on mobile — which is where most people read email. Front-load your most compelling words.
Using spam trigger words
Words like "FREE!!!", "Guaranteed", "No risk", "Act now", and "$$$ Cash $$$" trigger spam filters. Even legitimate emails can land in junk if you're not careful.
Clickbait that doesn't deliver
A sensational subject line that doesn't match the email content destroys trust fast. Subscribers will open once — and then unsubscribe or mark you as spam.
Never testing
If you always use the same style, you'll never discover what your specific audience responds to. A/B testing even just once a month can compound improvements over time. MailerLite, Moosend, and ActiveCampaign all include built-in split testing at no extra cost.
Ignoring the preheader
The preheader (preview text) appears right next to your subject line in most inboxes. Leaving it blank means your email client pulls random text from your email body, which often looks terrible. Write a preheader that completes or adds to the subject line.
Keep Learning
Subject lines are just one piece of the puzzle. These guides cover the rest.
Email Marketing for Beginners
The complete starter guide — everything from list building to your first campaign
Email Welcome Series Examples
Copy-ready 3 and 5-email welcome sequences for any business
Best Newsletter Platforms
The top platforms compared by features, pricing, and ease of use
Email Marketing Automation Examples
Real workflows you can copy — welcome, abandoned cart, re-engagement, and more
9. Frequently Asked Questions
The most common questions about writing email subject lines.
Ready to Send Better Emails?
Now you have the formulas, examples, and mistakes to avoid. Pick a platform with built-in A/B testing and start experimenting with your own subject lines today.
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