How to write a cold email for a marketing agency

You run a small agency, you sent cold emails that said "we help businesses grow", and almost nobody wrote back. Here is how to write a cold email for a marketing agency that owners answer: open with one fix you found on their marketing, add one honest line of proof, and offer a free 5-minute video, under 80 words, then send 100 a day. A template about your services, with an audit attached, reads like every other agency pitch in their inbox, and no case studies makes it easy to ignore.

Do these three things

About 6 hours a day, every day, next to client work. Judge each version after 1,000 people, and which fix to keep after 2,800.

Show the three actions in fullHide the full list

1. 1Today: pick one kind of client and three fixes you can spot on their marketing in 3 minutes. Then write one cold email under 80 words: the fix as the first line, one honest line of proof, and an offer of a free 5-minute video.
2. 2Every day: send 100 of these emails, one at a time, to owners on your lead list, each opening with a fix you checked on that business. AI drafts; you write the first line. Follow up 3 times, and record the video only for people who say yes.
3. 3Every Sunday: count conversations per 100 people for each fix. After 1,000 people on one version, keep it if 1 or more in 100 became a conversation. If not, change one part, in this order: the list, the fix, then the offer.

Get help doing these

ChatGPT or Claude reads this guide and works through it with you.

Do this with ChatGPT(opens in a new tab)Do this with Claude(opens in a new tab)

1. Pick one kind of client and three fixes you can spot in 3 minutes

Write one sentence that says which businesses you email, then pick three problems you can spot on their marketing from the outside in 3 minutes or less. These three fixes become the first line, the subject and the offer of every email, so one email does one job.

Start with the sentence. It is the short form of your ideal customer profile, and if you have not picked a niche for your agency yet, pick one now, the same one you use to market your agency: one email cannot fit a dentist, a SaaS founder and a shop. Email the owner or founder of a business with fewer than 50 people. In Belkins' 2026 study of 7.5 million cold emails sent in 2025, founders and owners replied more than any other job level, and companies of 10 people or fewer replied three times as often as companies of 10,000 or more.

The owner or founder of a [kind of business] with [size], who [the moment marketing hurts: no new enquiries, a launch coming, a first marketer leaving].

Then pick three fixes from this list. Pick ones that lead straight to the work in your package: if you sell ads, pick ad fixes; if you sell content, pick content fixes.

AI answers are the newest fix, and few owners have checked them yet. In G2's March 2026 survey of 1,076 buyers, 51% of business software buyers started their research in an AI chatbot more often than in Google, up from 29% a year before. That is the start of AI visibility work you can sell, and of getting a client mentioned by ChatGPT.

If your clients are local businesses: use AI answers and the Google listing as two of your three. In BrightLocal's 2026 survey of 1,002 US adults, 45% had used ChatGPT or other AI tools for local recommendations, up from 6% a year before. What a good listing has is in setting up a Google Business Profile and getting Google reviews.

If you run ads for clients: use the three ad libraries. They show which ads a business runs now, so you can point at one ad and one fix, the work you would do when you run their Facebook ads or LinkedIn ads.

• Tool: a Google Doc, and ChatGPT or Claude (both have free plans).
• Time: 45 minutes.
• You will have: one sentence and three fixes, each with a pass or fail check.
• It worked if: you can check all three fixes on 5 real businesses in 15 minutes, and at least 1 in 3 of them fails one.
• Common mistake: fixes that need a login or are only your opinion, such as "your branding feels weak" or "your SEO could be better". The owner cannot check those, so they cannot agree with you.

2. Find one fix on each business before you write a word

Before you write to a business, check it against your three fixes and write down the first one that fails, with the exact fact you saw. That fact is your first line, so no fix means no email.

Do this for every row you add to your lead list. Check the fixes in the same order every time, and stop at the first one that fails. Write what you saw in plain words: "not named when I asked ChatGPT for the best scheduling app for dental clinics", not "AI visibility low".

Speed it up in three ways:

• Ask AI once for many businesses. One question to ChatGPT, such as "What is the best [kind of software] for [buyer]?", checks every business in that category at once. Write down the date and the exact question.
• Open each ad library once a day and search the businesses in a batch.
• Let AI read the homepage, but check it yourself. You can paste a homepage into ChatGPT or Claude and ask what the business does, but open the page and see the fact yourself before it goes in the sheet. AI gets these wrong.

Find the owner's name and work email at the same time: you want the decision maker, not an info@ inbox. Many small businesses list one on their site; for the rest, find the decision maker's email with Hunter. Its free plan gives 50 credits a month; at 100 names a day you need Starter, $49 a month or $34 a month billed yearly, for 2,000 credits.

Business | Website | Owner | Email | Fix | What I saw (date) | Date sent | Follow-up 1 | Follow-up 2 | Follow-up 3 | Reply | Next step

• Tool: Google Sheets, the business's website, ChatGPT or Claude, the three ad libraries, Google Maps, and Hunter.
• Time: about 90 seconds a business, so about 2 hours 30 minutes for 100 a day.
• You will have: 100 new rows a day, each with an owner, an email and one fix you saw yourself.
• It worked if: every row has a fact the owner could confirm in 10 seconds, and fewer than 2 in 100 emails bounce.
• Common mistake: writing the email first and looking for a reason later, or pasting a fact AI suggested without opening the page. One wrong fact ends the conversation.

3. Open with the fix, as a fact they can check in 10 seconds

The first line of your agency cold email says what you saw and where, in one or two plain sentences, with no insult and no compliment. It proves the email was written for them, and it shows your skill before you say a word about yourself.

Say the fact, then stop. Let them draw the conclusion. "Your homepage headline says 'AI-powered workflow engine'" is a fact they can check. "Your homepage is confusing" is a verdict, and owners argue with verdicts.

AI answers: I asked ChatGPT for the best [their kind of software or service] for [their buyer]. It named [number] [tools / businesses]. Yours was not one of them.Homepage: The headline at the top of your homepage says "[their exact words]". I could not tell who it is for until I scrolled.Ads: [Two competitors] run ads on [Facebook / LinkedIn / Google] right now. I could not find any of yours.Google listing: Your last [number] Google reviews have no reply, including [one short, kind detail from a review].Posts or blog: Your last [post / article] was on [date].

Write this line yourself. Since 8 January 2026, Gmail's Help Me Write has been free for everyone, so owners get more sales emails that all sound the same. In Hunter's 2026 survey, 69% of US decision makers said it bothers them if AI wrote the email, and 67% said a detail from public information makes them more likely to reply. A line about their marketing, which you checked, is the one thing no AI template has. If replies stay low, the first line is what getting more replies fixes first.

• Tool: your sheet, and your own words.
• Time: about 30 seconds a person, with the fact already in the sheet.
• You will have: a first line for every person you email today.
• It worked if: each line could only go to that one business, says where you saw the fact, and would not embarrass you if they forwarded it to their team.
• Common mistake: "I came across your company and was impressed", which fits anyone, or "your website is outdated", which insults the person you want to work for.

4. Add one honest line of proof and offer a free 5-minute video

After the first line, write one sentence on what you do for whom, one honest line of proof, and one question that offers a free 5-minute video showing how you would fix what you saw. You write this middle once for each fix and use it in every email.

The proof line. Use the strongest true line of social proof you have. Prospects asking for case studies you do not have yet is the most common worry new agency owners post about. This rule tells you what to write:

• You have 1 or more clients: say what you do for them, by kind and size: "I run LinkedIn, content and ads for two small SaaS companies." Add a number only if it is true and the client agreed. Ask each client for a short testimonial so you have a better line next month.
• No clients, but you did this work in a job: "At my last job I ran [the work] for [kind of business]." Do not present your old employer's results as your agency's.
• Nothing yet: let the fix be the proof, and say so plainly: "I'm starting with [kind of business], so the video is free."

Never invent a client, a result or a quote. In the US, the FTC's rule against fake testimonials, in force since 21 October 2024, also covers claims that misstate what a customer experienced. Getting agency clients without case studies covers how to build real proof fast.

The offer. Offer a free video of 5 minutes or less that shows how you would fix the one thing you saw. Ask first, and record it only for a yes. Put no link and no attachment in this first email: a stranger will not open a file, and an unrequested audit is the email they have learned to delete. When someone says yes, record it with Loom's free Starter plan, which allows 5-minute screen recordings and 25 videos; delete old ones as you go. Leave out your calendar link and your price too. Hunter found that open questions work better than asking for a meeting, and 65% of decision makers said cold emails fail because they feel too sales-focused.

I [what you do] for [kind of business]. [One honest line of proof.]Want me to record a free 5-minute video showing [the one change you would make]? No call needed.

• Tool: your Google Doc. Loom (free) for later.
• Time: 20 minutes, once for each fix.
• You will have: three middles, one for each fix.
• It worked if: each middle is under 45 words, its proof is true today, and it ends in one question that can be answered "yes".
• Common mistake: a list of every service you offer, an invented result, or "Can we hop on a 30-minute call?" as the ask.

5. Write a 4 to 6 word subject that names the fix, then cut to 80 words

Write a subject line of 4 to 6 plain words that names their business and the fix, then add your name, postal address and a way to say no, and cut the whole email to under 80 words. Read it on your phone before you send it.

Use lower case, like a note to a colleague. In Hunter's study of 31 million emails sent in 2025, subject lines of 5 to 6 words got the most replies, and "Quick question" got fewer replies than other subjects.

[their company] in ChatGPT
[their company] homepage headline
your [Facebook / LinkedIn] ads and [their company]
[their company] Google reviews

The footer is the law. In the US, the CAN-SPAM Act "makes no exception for business-to-business email". Every email needs a true From name, a subject that does not mislead, a clear sign that you are selling something, your postal address and a way to say no, and you must honour a "no" within 10 business days. Each email that breaks the rules can cost up to $53,088. Never write "Re:" or "Fwd:" on a first email. In the UK you may email companies without asking first, but sole traders and some partnerships count as people and must have agreed, and many small local businesses are sole traders (step 6 says what to do instead). The UK guidance is under review after the Data (Use and Access) Act 2025. In the EU, rules differ by country, so check them before you email owners there.

Then cut. In Instantly's benchmark of cold email sent in 2025, the best campaigns kept emails under 80 words. Send plain text: no logo, no images, no attachments, no links. Check that your website and your LinkedIn profile say who you help in one line, because most owners look you up before they reply.

Subject: [their company] + [the fix, in 2 or 3 words]Hi [first name],[First line: the fix you saw, and where.]I [what you do] for [kind of business]. [One honest line of proof.]Want me to record a free 5-minute video showing [the one change]? No call needed.[Your name], [agency], [phone]
[Postal address]
Not for you? Reply "no" and I won't write again.

• Tool: Gmail and any free word counter.
• Time: 20 minutes, once.
• You will have: one finished email for each fix, ready to change for each person.
• It worked if: it is under 80 words above your name, fits one phone screen, and has no link and no attachment.
• Common mistake: no postal address and no way to say no. In the US that breaks the law, even for business email.

6. Send 100 agency cold emails a day and follow up 3 times

Every day, send 100 of these emails to owners on your list, one at a time, each with its own first line. Follow up with everyone who does not answer, 3 times, in the same thread.

100 a day sounds like a lot. It is the point, and the same target as getting your first agency client. In Instantly's 2025 benchmark, the average reply rate was 3.43%, counting every reply, including "no". At 30 emails a day, a reply rate like that brings about one answer a day, too few to learn anything in a month. At 100 a day you get 2 or 3, and after 1,000 people, about 10 days, you know whether the email works.

Let AI draft, you write line 1. Paste 10 rows from your sheet into ChatGPT or Claude, each with the owner's name, business, fix and what you saw, plus your email from step 5. Ask for one email per row, under 80 words, changing only the subject and the first line. Rewrite each first line in your own words, check the fact once more, and send. That is about a minute an email.

Send safely, and spread the 100. Gmail requires every sender to have SPF or DKIM, two settings that prove an email really comes from your domain, and to keep spam reports below 0.3%. Since November 2025, Gmail has been rejecting more mail that breaks these rules. Send cold email from a second domain you have warmed up, never from the address your clients use, and send no more than about 30 emails a day from each warmed mailbox, follow-ups included. Send the rest of the 100 as LinkedIn messages or phone calls, with the same first line and offer. On a free LinkedIn account you can add a note to only 3 connection requests a month, so send requests without a note and message owners once they accept; getting agency clients on LinkedIn has the details. In SmartReach's 2026 report, campaigns that used email, LinkedIn and calls together booked 21 meetings per 1,000 people, against 8 for email alone. Do not lower the 100.

If your clients are UK sole traders, such as many local trades and salons: do not cold email them. Call them, or message their business page, with the same first line and offer.

Write every day; send on their working day. On days your owners are closed, write the day's emails anyway. In Gmail, click the Down arrow next to Send, then Schedule send, and pick their next working morning. Gmail holds up to 100 scheduled emails.

Follow up 3 times. Reply in the same thread on day 3, day 7 and day 14, each with one new line: a quick tip they can use today, or a second fact. In Instantly's data, 42% of replies came after the first email. Stop the moment someone answers. Following up on a cold email has the three emails.

• Tool: Gmail from your warmed mailboxes, ChatGPT or Claude, LinkedIn, your phone, and your sheet. A CRM can wait until the sheet gets slow.
• Time: about 1 hour 40 minutes a day for 100 first emails, and about 1 hour for the follow-ups that are due. Block the same hours every day, before client work.
• You will have: 700 first emails a week, each logged with its follow-up dates.
• It worked if: 100 go out every day, each with its own first line, and fewer than 2 in 100 bounce. More bounces mean the addresses are wrong: fix the list before you send more.
• Common mistake: pasting the same email into a bulk tool and sending 500 at once from a new domain. In Hunter's 2025 data, campaigns to 21 to 50 people got 6.2% replies, and campaigns to more than 500 got 2.4%.

7. Answer every reply the same day, even a request for case studies

Answer every reply on the day it arrives, with a short, honest email that moves the person one step: from yes to video, from video to a call. Most replies are one of four kinds, so write your four answers once.

Record the video within 24 hours of a yes. Show the one thing you saw, the change you would make, and what it should lead to, in under 5 minutes. Then offer a 20-minute call with two times to choose from. After the call, send a written proposal the same day, with a clear scope of work, so the first month starts without arguments about what is included.

Yes: Thanks, [first name]. I'll send it by [day]. Is [the page / the ad / the listing] the one you care most about?The video (when it is ready): Here's the video: [link]. The short version: [the one change]. If you want, I can walk you through the rest on a 20-minute call. [Day and time] or [day and time]?"Do you have case studies?": Fair question. I don't have a write-up yet. What I do have: [your honest proof line]. The video is the best way to judge my work, because it shows exactly what I'd change for [their company]. Want it?"How much?": My [package name] is $[price] a month, with a paid first month and no long contract. Whether it's worth it depends on [the fix], and the video will show you. Want it?"We already have someone": Good to hear. Would the video still be useful to them? If not, may I check back in 3 months?

Give your price when they ask. Hiding it after a direct question loses trust. Your package and its price come from packaging your services; if you sell social media, price social media management from your hours. If someone says no, mark them in your sheet and never write again. If they say "not now", ask whether you may write in 3 months and put the date in your sheet; that is the start of nurturing a lead.

When someone signs, onboard them the same week, and agree how they will approve your work before anything goes live.

• Tool: Gmail and Loom (free).
• Time: about 1 hour a day for replies and videos, more on good days.
• You will have: an answer to every reply, sent the same day, and a video for every yes.
• It worked if: every yes has its video within 24 hours, and every reply is marked in your sheet with its next step.
• Common mistake: going quiet after "how much?", sending a 20-page deck to "do you have case studies?", or recording videos for people who never asked.

8. Count conversations per 100 emails for each fix every Sunday

Every Sunday, count how many people you emailed, how many replied and how many became conversations, for each fix. A conversation is a yes to the video, a real question back, or a call. After 1,000 people on one version, keep it or change one part.

Count replies, not opens. Apple's Mail Privacy Protection hides whether people opened your email, so open rates are wrong for many readers. Turn off open tracking if your tool has it. In Hunter's 2025 data, emails sent without open tracking got 7.4% replies, against 4.4% with it.

Week | Fix | Version | People emailed | Replies | Conversations | Per 100 | Bounces | What I changed

After every 1,000 people on one version, use this rule:

• 1 or more conversations per 100 people: keep it. Spend the time on the calls and proposals that follow.
• Fewer than 1 per 100: change one part, then send the next 1,000. First the list: are these the owners in your step 1 sentence? Then the fix: swap it for another one from step 1. Then the offer: make it smaller, such as a 2-minute video of one change.
• Replies, but almost no conversations: the people are right and the offer is wrong. Make it smaller.

After 2,800 people, about 4 weeks, put most of your 100 a day on the fix that brought the most conversations, and test one new fix in place of the weakest. If every fix brings fewer than 1 conversation per 100 after 3,000 people, go back to your niche: the owners may not pay for marketing yet. Then track which channel brought each client, so you can compare cold email with Upwork and the other ways you find clients online. Once a month, look at all of it in a marketing review.

• Tool: Google Sheets.
• Time: 20 minutes every Sunday.
• You will have: one row per fix per week, and a clear answer on which fix opens doors in your niche.
• It worked if: you can say how many conversations you get per 100 people for each fix, and what caused each change.
• Common mistake: judging after 50 emails, judging by opens, or changing the fix, the proof and the offer all at once.

Your agency cold email checklist

0 of 13 done

Work through this list with an AI assistant

It drafts the work and keeps track of what is done.

Do this with ChatGPT(opens in a new tab)Do this with Claude(opens in a new tab)

Step 1 · Pick one kind of client and three fixes

• Write one sentence on which owners you email: kind of business, size and the moment marketing hurts.
• Pick three fixes you can spot from the outside in 3 minutes, each leading to work you sell.

Step 2 · Find one fix on each business

• Every dayAdd 100 owners to your sheet, each with one fix you saw yourself.

Step 3 · Open with the fix as a fact

• Write a first line for each of your three fixes, saying what you saw and where.

Step 4 · Add proof and offer a 5-minute video

• Write the middle for each fix: what you do, one honest line of proof, and an offer of a free 5-minute video.

Step 5 · Write the subject and cut to 80 words

• Write a 4 to 6 word subject for each fix, add your postal address and a way to say no, and cut each email under 80 words.

Step 6 · Send 100 a day and follow up 3 times

• Set up your sending: a warmed second domain, and a split of the 100 across email, LinkedIn and phone.
• Every daySend 100 first emails, one at a time; AI drafts, you write each first line.
• Every daySend the follow-ups due today, up to 3 per person.

Step 7 · Answer every reply the same day

• Every dayAnswer every reply the same day with the right one of your four answers.
• Every dayRecord and send a video for every yes within 24 hours.

Step 8 · Count conversations per fix every Sunday

• Every SundayFill in one row of the Sunday sheet for each fix.
• After 1,000 peopleKeep the version, or change one part: the list, then the fix, then the offer.

Copy listDownloadReset