Email Subject Lines for Outreach: 50 Examples That Get Replies
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Your subject line decides whether the email gets opened. Below are 50 examples, grouped by goal, plus the 5 rules that make them work. Jump to what you need:
| Your goal | Jump to |
|---|---|
| Pitching a guest post or backlink | Link building (10) |
| Booking a sales meeting | Sales prospecting (10) |
| Following up on no reply | Follow-ups (8) |
| Pitching a journalist | Digital PR (6) |
| Networking after an event | Networking (6) |
| Pitching a partnership | Partnership (5) |
| Reviving silent prospects | Re-engagement (5) |
Score any subject line in seconds with our free Subject Line Tester.
The 5 rules that beat any template
| Rule | Why it works |
|---|---|
| 3–7 words, 30–50 characters | Fits mobile preview, where most B2B opens happen |
| Lowercase or sentence case | Reads like a real human, not a marketing blast |
| One specific reference | Their name, post, product, or city signals real research |
| No spam words | "Free", "guaranteed", "limited time" hurt deliverability |
| Promise the email body | The subject sets up what's inside, no bait-and-switch |
1. Link building & guest post outreach
For pitching blog editors and authors. Pair these with the bodies in our link building email templates and guest post pitch templates.
1. Idea for [their site name]
2. Loved your post on [topic]
3. Small fix on [article URL slug]
4. Quick add for your [topic] guide
5. Broken link on [page]
6. Guest post pitch: [angle in 4 words]
7. Resource for your [topic] roundup
8. [Their name], one thought on your [topic] piece
9. Updated stat for your [year] post
10. Link suggestion: [their post]
2. Sales prospecting & cold sales
Short, specific, and never "checking in." Use with the bodies in our sales prospecting templates.
11. Quick question about [their product]
12. [Mutual contact] suggested I reach out
13. 3 ideas for [their company]
14. Saw your [funding/launch/hire] news
15. [Competitor] just shipped [feature], your take?
16. [First name], 90 seconds?
17. Worth a chat about [specific outcome]?
18. One question on [their workflow]
19. Idea after reading your [report/post]
20. [Company] + [your company]?
3. Follow-up subject lines
Always reply on the original thread when possible. For the body, use our follow-up email templates.
21. Re: [original subject]
22. Did this miss you?
23. Bumping this up
24. One more thought on [topic]
25. Quick nudge, [first name]
26. Should I close the loop?
27. Last note on [topic]
28. New angle for [their goal]
4. Digital PR & journalist pitches
Reporters scan inboxes by topic, so lead with the angle, not your brand. See our how to pitch media guide for the full pitch structure.
29. Story tip: [angle in 5 words]
30. Data: [specific stat]
31. Source for your [beat] coverage
32. [Trend] is changing, here's why
33. Exclusive: [topic] data, embargoed
34. Reaction quote on [breaking story]
5. Networking & introductions
For warm intros, conference follow-ups, and "nice to meet you" emails. See our pleasure meeting you email templates for full bodies.
35. Great meeting you at [event]
36. Following up from [conference]
37. Re: introduction, [your name] <> [their name]
38. Coffee in [city] next week?
39. Thanks for the intro to [name]
40. Re: our chat at [booth/session]
Which subject line is most likely to get opened by a busy B2B founder?
Correct. Specific, short, and clearly relevant to the recipient. The other two are either spammy or so vague they read as a mass blast.
"Idea for your onboarding flow" wins. It's short, specific, and signals real research. ALL CAPS plus "FREE" trips spam filters, and "Quick check-in" is too generic to earn an open.
6. Referral & partnership outreach
Use these for affiliate, co-marketing, and integration pitches. The bodies live in our business partnership email templates and referral email template guides.
41. Co-marketing idea: [your brand] + [theirs]
42. Referral: [name] could use [their product]
43. Audience swap idea
44. Integration request from [your company]
45. Affiliate program for [their tool]?
7. Re-engagement & win-back
For prospects who went silent or trial users who churned.
46. Still on your radar?
47. Should I close your file?
48. One last try, [first name]
49. New for you: [feature/result]
50. Worth reopening this?
Stop guessing subject lines
MentionAgent writes a personalized subject line for every prospect, based on the blog post you're pitching. You approve every send.
Start FreePatterns that consistently win
- Question format. "Worth a chat about X?" "Quick question on Y?" Open-loop wording earns the open.
- Reference + idea. "Loved your post on X, small idea." Pairs proof of reading with a reason to reply.
- Lowercase first word. Reads like a 1:1 email, not a campaign. Personalization beats polish.
- Their name, not yours. Lead with their company or article slug. Your brand belongs in the signature.
- One specific token. Their post title, city, funding round, or hire. Generic merge tags don't lift opens.
Good vs. bad: side by side
| Bad | Good | Why |
|---|---|---|
| Following up | Should I close the loop? | Open question beats vague status |
| Touching base | One more thought on [topic] | Adds value, not pressure |
| HUGE OFFER!!! | Idea for your onboarding | Specific, no spam triggers |
| Hi {first_name} | Loved your post on [topic] | Real reference, not a merge tag |
| Quick Question About Your Marketing | quick question on your pricing page | Sentence case reads 1:1 |
Patterns to avoid
- "Following up" or "Touching base" with no context
- Title case for every word ("Quick Question About Your Product")
- Emoji in the first 30 characters, gets flagged in B2B filters
- Multiple exclamation points or all caps
- Anything that promises something the email body can't deliver
- Words that trigger spam filters like "free", "guarantee", "winner"
A prospect ignored your first email. What's the best follow-up subject line?
Correct. Replying on the original thread keeps context, and adding a new angle gives the recipient a real reason to re-engage.
"Following up" and "Just checking in" add zero new value. The third option keeps thread context with Re: and pairs it with a fresh angle, which is the only reason a busy prospect reopens a stalled thread.
You're pitching a guest post. Which subject line should you send?
Correct. It tells the editor exactly what's coming and shows you have a specific angle. That's how guest post pitches earn replies.
The middle option wins. Editors filter on subject. Show them the angle, skip the hype, and they'll click through to read the pitch.
How to test before you send
Send to yourself on Gmail, Outlook, and a mobile inbox. Check three things:
- Truncation: Does the full subject show on a phone, or does it cut off at the important word?
- Preview pane: What does the first sentence of the body show next to the subject? They should reinforce each other.
- Spam tab: Did it land in promotions or spam? If yes, swap any flagged words and rewarm the sending domain. Our cold email tools roundup covers warmup options.
For a numeric score on length, personalization, power words, and spam triggers, paste yours into the Email Subject Line Tester.
Frequently asked questions
What is the best subject line for a cold outreach email?
The best cold outreach subject lines are short (3 to 7 words), specific to the recipient, and reference something they care about. Question-format subjects like "Quick question about [their product]" and reference subjects like "[Their article] + a small idea" consistently get the highest open and reply rates.
What are eye-catching email subject lines?
Eye-catching subject lines stand out by using curiosity, specificity, or a personal reference. Examples: "Idea for [company]", "Loved your post on [topic]", "3 ways to fix [their problem]". Skip clickbait, all caps, and excessive punctuation, which trigger spam filters and damage trust.
How long should a professional email subject line be?
Keep professional subject lines between 30 and 50 characters or 3 to 7 words. That length displays in full on most mobile inboxes, where many B2B emails are first opened. Anything over 60 characters typically gets truncated.
Do personalized subject lines really get more opens?
Yes, when the personalization is genuinely specific. The lift comes from relevance, not the merge tag itself, so referencing a recipient's actual blog post or product detail performs much better than a generic "Hi {first_name}" merge.
What words should I avoid in a subject line?
Avoid spam triggers like "free", "guaranteed", "act now", "limited time", and "winner". Skip ALL CAPS, multiple exclamation points, and money symbols. These hurt deliverability and signal a generic blast rather than a real outreach email.
Should I use emoji in a B2B outreach subject line?
Usually not. Emoji works for consumer newsletters and creator marketing, but in B2B outreach it often reads as a marketing blast and can be flagged by stricter corporate spam filters. If you do use one, place it at the end, not the start, and only when it adds real meaning.
Is it okay to use "Re:" if there was no previous thread?
No. "Re:" on a thread that never existed is misleading and may violate CAN-SPAM, which prohibits deceptive subject lines. Only use "Re:" when you're actually replying to a real prior message in the same thread.
Should I A/B test subject lines on a small list?
On small outreach lists (under a few hundred prospects) A/B testing rarely produces statistically meaningful results, so you'll be guessing either way. Pick the subject line that's most specific to the recipient and ship it. Save A/B testing for high-volume, opted-in campaigns where you have enough data.
Does title case or sentence case work better?
Sentence case usually feels more like a 1:1 email. Title case ("Quick Question About Your Marketing") reads like a campaign subject because that's where most readers see it. Sentence case or lowercase signals a real person on the other end.