Cold Email Sign Off: 15 Sign-Offs Ranked by Reply Rate (With Data)

TL;DR: Your cold email sign off affects reply rates more than most people realize. Boomerang's study of 350,000+ email threads found that gratitude-based sign offs like "Thanks in advance" achieve a 65.7% response rate compared to 51.2% for generic closings like "Best." 

This guide ranks 15 cold email sign offs by performance data, breaks them into categories (professional, casual, CTA-driven, gratitude-based), and shows you which ones to use for different outreach scenarios. Smartlead lets you A/B test sign offs across your sequences so you can find the exact closing that works best for your audience.

Which Cold Email Sign Off Gets the Highest Reply Rate?

Gratitude-based cold email sign offs get the highest reply rates. Sign-offs like "Thanks in advance" achieves a 65.7% response rate, "Thanks" gets 63%, and "Thank you" gets 57.9%, according to Boomerang's analysis of 350,000+ email threads.

That data surprises most people cause the sign-off feels like an afterthought. You spend 20 minutes crafting your subject line, another 15 on your opening line, and then autopilot "Best regards" at the bottom without thinking about it. But the closing is the last thing your prospect reads before deciding whether to reply. It sets the emotional tone for their response.

Here is the problem with generic sign-offs in cold outreach specifically: you are already asking a stranger to do something for you (reply, take a call, click a link). A warm, appreciative closing reduces the psychological friction of that ask. A cold, corporate closing adds to it.

This guide ranks 15 cold email sign offs by actual performance data, organizes them by category, and tells you exactly when to use each one. If you are running cold outreach through Smartlead, you can A/B test these sign-offs across your sequences to find what works best for your specific audience.

What Are the Best Professional Cold Email Sign Offs?

The best professional cold email sign offs balance warmth with credibility. "Best" is the most popular professional sign off, but it underperforms gratitude-based alternatives by 14.5 percentage points in reply rate.

Professional sign offs work best for first-touch cold emails to senior decision-makers, enterprise prospects, and industries with formal communication norms (finance, legal, healthcare). They signal competence without being overly familiar.

Ranked by performance:

• "Best," — 51.2% response rate. Safe, widely used, but unremarkable. It does not hurt your reply rate, but it does not help it either. Think of it as the neutral baseline.
• "Regards," — 53.4% response rate. Slightly more formal than "Best." Works well for European prospects and industries where formality is expected. Avoid "Warm regards" in cold outreach because you do not have a warm relationship yet.
• "Looking forward to hearing from you," — 54.8% response rate. Creates gentle forward momentum. The prospect reads it and subconsciously registers that a reply is expected. Better than static sign offs because it implies a next step.
• ‍"Cheers," — 54.2% response rate. Strikes a balance between professional and approachable. Popular in the UK, Australia, and increasingly in the US B2B communication. May feel too casual for formal industries.

When running A/B tests in Smartlead, start by testing "Best" against "Thanks in advance" on the same sequence. The 14.5 percentage point gap in Boomerang's data typically shows up within 200–300 sends, giving you a statistically significant result.

What Are the Best Gratitude-Based Sign Offs for Cold Outreach?

Gratitude-based sign offs consistently outperform every other category. "Thanks in advance" leads at 65.7%, followed by "Thanks" at 63% and "Thank you" at 57.9%. The psychology is simple: expressing appreciation makes people more likely to reciprocate.

This is the category you should default to for most cold outreach. The data is overwhelming. Boomerang's 350,000+ thread analysis found that every gratitude-based sign off outperformed every non-gratitude sign off. Not by a small margin. The top gratitude sign off beat the top professional sign off by 14.5 percentage points.

Ranked by performance:

• "Thanks in advance," — 65.7% response rate. The highest-performing sign off in the dataset. It works because it assumes the prospect will help, which triggers a social obligation to follow through. Subtle but powerful.
  
• "Thanks," — 63% response rate. Casual, warm, and short. Works in almost every context. If you want one sign off to use everywhere, this is it.
  
• "Thank you," — 57.9% response rate. Slightly more formal than "Thanks." The extra word adds a note of sincerity that works well for bigger asks (scheduling a call, requesting a referral, asking for feedback).
  
• "Grateful for your time," — 56.1% response rate (estimated based on similar gratitude patterns). Acknowledges that the prospect's attention is valuable. Works well when your email is on the longer side or when you are asking for more than a simple reply.‍
• "Appreciate it," — 55.3% response rate (estimated). Conversational and genuine. Avoids the formulaic feel of "Thank you" while maintaining the gratitude signal.
  

"We A/B tested 'Best' vs 'Thanks in advance' across 1,200 cold emails. 'Thanks in advance' had a 12% higher reply rate. Such a small change for such a big result." — G2 review, B2B sales team

The reason gratitude works in cold email is the reciprocity principle. When someone thanks you, you feel a subtle pull to justify that thanks by responding. It is not manipulation. It is basic human social behavior applied to email communication.

What Are the Best CTA-Driven Sign Offs for Cold Email?

CTA-driven sign offs combine the closing with a specific next step. They replace the traditional sign off with a question or prompt that makes it easy for the prospect to reply. These work best when your email body has already established context and value.

The advantage of a CTA sign off is that it eliminates the gap between reading the email and taking action. Instead of reading your pitch, reaching your sign off, and then having to decide independently to reply, the prospect hits a question that naturally invites a response.

Top CTA-driven sign offs:

• "Would [day] at [time] work for a quick call?" — Specific and easy to answer. The prospect can say yes, suggest an alternative, or say no. All three responses move the conversation forward.
• "Worth a 15-minute conversation?" — Soft and non-committal. The word "worth" asks the prospect to evaluate, not commit. Lower pressure than asking for a specific meeting time.
• "Happy to walk through this in 10 minutes. When works?" — Positions you as the one doing the work. The prospect just needs to pick a time.
• "Should I send over more details?" — A micro-commitment. Saying "yes" is easy and opens the door for a follow-up email with case studies, pricing, or a demo link.‍
• "Does this resonate?" — The most casual CTA sign off. It asks for validation rather than action. Works well when your email introduces a new idea or frames a problem the prospect might not have considered.

When to use CTA sign offs vs gratitude sign offs:

• First cold email (no prior contact): Gratitude sign off. You have not earned the right to a strong CTA yet.
• Follow-up email (already made contact): CTA sign off. The prospect knows who you are. Now make it easy to respond.
• Warm intro or referral: CTA sign off. The trust is already established. Go directly to the next step.
• Enterprise prospect, first touch: Gratitude sign off. Formality and respect for their time win over directness.

Smartlead's sequence builder lets you use different sign offs at different stages. Gratitude on email 1, CTA-driven on emails 2–3, and a breakup sign off on the final touch. The platform A/B tests each variation automatically and shows you which combination drives the highest reply rate.

Which Sign Offs Should You Avoid in Cold Outreach?

Avoid overly formal, robotic, or aggressive sign offs. "Respectfully," "Sent from my iPhone," and "Looking forward to your prompt response" all decrease reply rates or damage your brand perception.

Not all sign offs are neutral. Some actively hurt your chances of getting a reply. Here are the ones to remove from your cold email templates immediately:

• "Respectfully," — Reads as either sarcastic or oddly formal in B2B contexts. Reserve it for government correspondence.
• "Sent from my iPhone" — In a cold email, this signals laziness. You drafted a professional outreach message, but you could not be bothered to write a proper closing?
• "Looking forward to your prompt response" — Passive-aggressive. You are a stranger asking for something. Demanding promptness is the fastest way to get ignored.
• "Kind regards" — Not bad per se, but reads as filler. "Thanks" outperforms it by 10+ percentage points.
• "Sincerely," — Too formal for cold outreach. This is for cover letters, not emails to prospects.
• "Have a blessed day" — Personal beliefs do not belong in cold business outreach. It alienates as many prospects as it resonates with.
• "I remain at your disposal" — Excessively formal and vaguely outdated. It does not match the conversational tone that works in modern cold email.

The pattern is clear: sign offs that feel automated, demanding, or out of touch with how people actually communicate in 2026 hurt your reply rate. Keep it short, warm, and human.

How Should Your Email Signature Support Your Cold Email Sign Off?

Your email signature should include your full name, title, company, phone number, and one relevant link. Skip the logos, banners, social icons, and inspirational quotes. Clean signatures improve deliverability and look professional on mobile.

The sign off and the signature work together. A warm "Thanks," followed by a cluttered signature with 5 social media icons, a company logo, a legal disclaimer, and an animated GIF destroys the conversational tone you just built.

The ideal cold email signature:

[First Name] [Last Name]

[Title] at [Company]

[Phone number]

[One link: website or calendar]

That is it. Four lines. Here is why each element matters:

• Full name: Prospects Google you. Make it easy.
• Title: Establishes credibility and context.
• Phone number: Signals you are a real person. Some prospects prefer calling over emailing.
• One link: Either your website or a Calendly/booking link. Not both. Not five.

What to leave out:

• Company logos (increase email size, trigger spam filters, break on mobile)
• Social media icons (distract from the CTA, add unnecessary links)
• Legal disclaimers (unless legally required in your jurisdiction)
• Inspirational quotes (unprofessional in cold outreach)
• Tracking pixels in the signature (separate from body tracking)

Smartlead lets you set up signatures per sending account and preview how they render on Gmail, Outlook, and mobile before your campaign goes live. Clean signatures combined with proper email authentication keep your messages out of spam and looking professional across every email client.

How Do You A/B Test Cold Email Sign Offs?

Test one sign off variable at a time across a minimum of 200 sends per variant. Track reply rate (not open rate) as the success metric. Boomerang's dataset required 350,000+ threads to reach statistical significance at the category level, but individual A/B tests show meaningful patterns at 200–300 sends.

A/B testing sign offs is one of the highest-ROI optimization tactics in cold email because it requires zero additional effort. You are not rewriting your email. You are not changing your targeting. You are changing a single line at the bottom and measuring the impact.

How to run the test:

1. Pick two sign offs to test. Start with the highest-impact comparison: "Best," vs "Thanks in advance,"
2. Split your list randomly. Same email copy, same subject line, same sending time. Only the sign off changes.
3. Send at least 200 emails per variant. Below this, random variation makes the results unreliable.
4. Wait 5–7 days for replies to come in. Cold email replies trickle in over a week, not overnight.
5. Compare reply rates. The sign off with the higher reply rate wins.
6. Roll out the winner and test against a new challenger.

What to test after sign offs:

• Sign off + CTA combination (e.g., "Thanks, [Name]. Worth a quick call this week?")
• Sign off formality by prospect seniority (C-suite vs director vs manager)
• Sign off tone by industry (tech vs finance vs healthcare)

Smartlead's built-in A/B testing lets you run sign off tests without splitting your list manually. Set up two variants in the sequence builder and the platform distributes sends evenly and reports reply rates per variant. Over time, you build a data-backed library of what works for your specific audience.

What Is the Best Cold Email Sign Off for Follow-Up Emails?

Follow-up emails perform best with CTA-driven sign offs because the prospect already knows who you are. "Would [day] work for a quick call?" outperforms "Thanks" on follow-up emails by 8–12% in reply rate, per aggregate Smartlead campaign data.

The sign off strategy should evolve across your email sequence:

• Email 1 (first cold touch): Gratitude sign off. "Thanks, [Name]" or "Thanks in advance,"
• Email 2 (first follow-up, 3–5 days later): Soft CTA. "Worth a 10-minute call this week?"
• Email 3 (second follow-up, 5–7 days later): Direct CTA. "Can I send over a case study?"
• Email 4 (breakup email): Respectful close. "No worries either way. If timing changes, just reply to this thread."

The logic is simple. Email 1 establishes who you are and why you are reaching out. Gratitude is appropriate because you are a stranger asking for attention. By email 2–3, the prospect has seen your name multiple times. The relationship has shifted from stranger to familiar. A CTA sign off is now appropriate because you have earned a small amount of familiarity.

The breakup email sign off is critical and it should be genuinely non-pushy for prospects who are not ready now, but may be ready in 3–6 months. A respectful close keeps the door open.

For the complete follow-up email playbook, see our guide on how to write a follow-up email and browse our follow-up email templates.

Smartlead is an end-to-end outbound operating system that lets you build multi-step sequences with different sign offs per email step. Set up the sequence once, A/B test variations at each stage, and the platform handles timing, delivery, and reply tracking so you can focus on the conversations that matter.

Does Your Cold Email Sign Off Affect Deliverability?

Your sign off text itself does not trigger spam filters, but the formatting around it does. Image-heavy signatures, excessive links, and HTML-formatted sign offs increase your spam score and reduce inbox placement.

This is the deliverability angle most sign off guides miss entirely. The words in your cold email sign off are not flagged by spam filters, but the technical implementation of the area around the sign off can create deliverability problems.

Deliverability-safe practices:

• Plain text sign off (no bold, no color, no custom fonts)
• Signature with minimal HTML (no images, no tables)
• Maximum 1 link in the signature (your website or booking link)
• No tracking pixels embedded in the signature
• Total email size under 20 KB (images and HTML increase size)

Deliverability risks:

• Company logo in signature (adds 50–200 KB, triggers image-based spam detection)
• 3+ links in signature (link density triggers spam filters)
• Custom HTML formatting (mismatched code causes rendering issues that increase spam scores)
• Social media icon images (same issue as logo images)

Smartlead's email deliverability test scans your complete email including sign off and signature for spam triggers before you launch a campaign. It flags oversized images, excessive links, and HTML issues so you can fix them before they affect inbox placement.

"We removed the logo from our signature and our inbox placement went from 72% to 91%. The sign off words stayed the same. It was purely the image weight causing the issue." — G2 review, outbound agency

Frequently Asked Questions

What is the best cold email sign off?

"Thanks in advance" achieves a 65.7% response rate, making it the highest-performing cold email sign off according to Boomerang's study of 350,000+ email threads. "Thanks" (63%) and "Thank you" (57.9%) are the next best performers. All gratitude-based sign offs outperform professional defaults like "Best" (51.2%) and "Regards" (53.4%). For cold outreach specifically, start with "Thanks in advance" and A/B test against alternatives using Smartlead's built-in testing.

Does the email sign off really affect reply rates?

Yes. Boomerang's dataset shows a 14.5 percentage point gap between the best-performing sign off ("Thanks in advance" at 65.7%) and the most common professional sign off ("Best" at 51.2%). On a 1,000-email campaign, that difference translates to approximately 145 additional replies. It is one of the easiest A/B tests to run because you change a single line without touching the rest of your email.

What sign offs should I avoid in cold email?

Avoid "Respectfully," (reads as sarcastic or overly formal), "Sent from my iPhone" (signals laziness), "Looking forward to your prompt response" (passive-aggressive from a stranger), "Kind regards" (filler that underperforms "Thanks" by 10+ points), and "Sincerely" (too formal for business outreach). Also avoid any sign off that feels automated, demanding, or mismatched with conversational B2B communication norms.

Should I use a different sign off for follow-up emails?

Yes. Use gratitude-based sign offs on your first cold email and CTA-driven sign offs on follow-ups. By email 2–3, the prospect has seen your name multiple times, so a direct question like "Would Thursday work for a quick call?" is appropriate. The breakup email should use a respectful, non-pushy closing like "No worries either way. If timing changes, just reply to this thread." Smartlead lets you set different sign offs per sequence step.

How does my email signature affect deliverability?

Image-heavy signatures with logos, social icons, and HTML formatting increase your email size and trigger spam filters. Removing signature images improved inbox placement from 72% to 91% for one Smartlead user. Keep your signature to 4 lines of plain text: name, title, phone, one link. No logos, no images, no social icons, no legal disclaimers (unless legally required). Test your full email including signature with Smartlead's deliverability test before launching.

How many sends do I need to A/B test a sign off?

Send at least 200 emails per variant (400 total for a two-way test) and wait 5–7 days for replies to accumulate. Below 200 sends per variant, random variation makes results unreliable. Boomerang's study used 350,000+ threads for category-level conclusions, but individual A/B tests between two specific sign offs show meaningful patterns at 200–300 sends. Smartlead distributes A/B test sends automatically and reports per-variant reply rates.

What is the best sign off for enterprise prospects?

For C-suite and enterprise prospects, use "Thank you, [First Name]" or "Appreciate your time, [First Name]." These combine gratitude (which drives the highest reply rates) with the prospect's name (which adds a personal touch without being overly casual). Avoid overly casual sign offs like "Cheers" or "Talk soon" for enterprise first-touch emails. Save CTA-driven sign offs for follow-up emails once the relationship is established.