Comprehensive Guide: Executing a 10,000 Cold Email Campaign

Created On:
November 26, 2023
Updated On:
February 26, 2024
send 10000 cold emails at once

Gmail, Outlook, and Yahoo don’t allow more than 500 cold emails per day. With a Google Workspace account, you can send up to 2000 emails. But that’s the limit. 

To send 10,000 cold emails at once without landing in spam (and also make money with it), you need a strong cold email tool like Smartlead

In addition, you need 68 secondary domains, 200 email accounts (3 email accounts per secondary domain) to send 10,000 email messages. 

In this article, you’ll find:

  • Things you need to do to send 10000 outreach emails
  • How to send 10000 outreach emails

Let’s dive in. 

Things You Need to Do Before Sending 10000 Cold Emails

For this part, I am guessing you already have a primary domain and a few email addresses. 

Example: our primary domain is, and its email addresses are,, etc. 

If you don’t have a primary domain yet, buy one before going to the next part. 

Sign Up on a Cold Email Tool - Smartlead 

If you're thinking how to send bulk cold emails, the first thing you need is a cold emailing software, such as Smartlead. Smartlead lets you add unlimited email accounts, warm up, create cold email campaigns, set follow-ups, schedule bulk emails, etc.  

One of our customers achieved as high as 19% positive reply rate with Smartlead.

Make a list of your needs and set a budget. Go through the features of a cold email tool and see if those align with your needs before buying a cold email tool. 

Not to beat our own drums, but Smartlead is the best option in the market right now. Check this out to learn why. 

Buy Secondary Domains & Create 200 Email Accounts

Number of secondary domains and email accounts  required to send 10000 emails per day

Secondary domains are additional domain names that a business or individual gets to complement their main domain. 

For example, our primary domain is, but our secondary domains are 


Secondary domains are vital in sending bulk cold emails for 2 reasons: 

  • Firstly, they help divide the email-sending load, improving deliverability.
  • Secondly, instead of using the primary domain and risking its reputation, you can use the secondary domains. This strategy will prevent potential blacklisting issues of the primary domain.

How many secondary domains do you need for 10,000 cold emails?

If you're thinking how to send 1000 cold emails or more, always split your bulk emails into batches—a max of 50 emails per address

Let’s get into a little math to find the answer to this question. 

You want to send 10,000 emails per day. If you can only send 50 emails per address, you will need 200 email addresses (simply 10,000 by 50) to send 10,000 emails.

Now, it’s recommended to create only 3 email addresses per secondary domain. 

So, divide 200 by 3. You need  66 to 67 secondary domains. We always recommend buying one or two extra domains. So, buy around 68 secondary domains to send 10,000 mails. 

Similarly, if you're wondering how to send 5000 cold emails, you will need 33 to 34 secondary domains and 100 email addresses.

To send 1000 cold emails, 6 to 7 secondary domains are enough with 20 email accounts.

Add Bulk Email Accounts to the Cold Email Tool

add bulk email accounts to cold email platform

Once you’ve the secondary domains and the 200 email accounts, add them to your cold email tool.

If you’re using Smartlead, check out this article for technical assistance. 

Email Authentication - DKIM, SPF, DMARC, and MX Records

SPF- Sender Policy Framework 

DKIM - Domain Keys Identified Mail 

DMARC - Domain-based Message Authentication, Reporting & Conformance. 

MX Record - Mail Exchange record

These abbreviations often confuse the daylights out of SDRs, but that’s okay. You’re not alone. Here’s an article on DKIM, SPF, DMARC, and MX Records to help you with everything related to it. 


Warming up email accounts is a must to see success with cold emails, especially when you’re using new domains and sending 10,000 messages.

Warm up your new email accounts for at least 2 weeks before launching the campaign. 

Here are resources to help you out with warm-ups:

For 10,000 messages, use a cold email tool with an AI-based warm-up feature. 

How to Send 10000 Cold Emails At Once

Sending 10,000 cold emails is similar to sending 100 emails. The difference lies in the number of secondary domains, the lead list, and how you segment and schedule it. 

Take a look at the cold email checklist and practices before launching your outreach campaign. It will save you from many evident mistakes. 

Let’s dig in. 

Create a Lead List 

The easiest way to create a lead list is to get a cold email tool that comes with a contact list building feature. 

For instance, with Smartlead, you can opt for this feature (Listkit integration) and create a targeted lead list with just a few clicks on the Smartlead app itself. 

If you want to use a separate platform for creating an email list, you have the below options: 

  • Databases
  • Email finders and scrapers

A database is a storehouse of info about potential customers. The information includes industry, contact details, company size, locations, and performance metrics. Using various filters, you can search these databases for potential customers that align with your ICP. is one of the most popular B2B databases. Here’s an article on How to use Apollo to create an effective email list

An email finder or scrapper is a tool designed to retrieve email addresses publicly posted on the internet. Popular email scrappers are Clay, GetProspect,,, etc.

Here are a few more resources to come up with a lead list:

Note: Always verify the lists before launching campaigns. Use Usebouncer, Bulkemailchecker, and MillionVerifier to verify the contacts. 

Upload the Lead List in CSV Format

Organise the downloaded lead list on a Google sheet or Excel doc using various columns to segment it properly. 

Now, log in to the Smartlead app and click on the ‘Email Campaign' section from the navigation menu. 

Add campaign option in a cold emailing tool

On Smartlead, you can either upload the lead list as a CSV file or import it directly from your CRM. 

Upload CSV file option in a ai outreach tool

Map the CSV Columns

Map CSV column

Next, connect each CSV column to the right dropdown option. If you have extra fields, like "Custom First Line," choose "Custom" in the dropdown. This way, you can include specific info not covered by the standard fields, making your data more personalised.

Afterwards, you will see a pop-up with a summary of the contact list, as shown below. 

file summary of an uploaded lead list

This summary is extremely crucial for bulk email outreach. Go through it and see if anything needs your attention.

Write the Email Sequence 

Once you click “Save & Next”, you will go to the next step—sequences. 

This is where you write the email body, subject line, and set the follow-ups for your 10,000-leads cold email campaign. 

When writing the email body, check out the “spam checker” section on Smartlead. It will show the words or terms that are likely to alert spam filters. 

Go through the results and improve your email copy accordingly. 

spam checker feature on Smartlead

Set Follow-Ups

Even though you’re sending 10,000 messages, it’s important to follow up to get the best results. 

Here’s how we follow up at Smartlead. 

set follow-ups on smartlead

Don’t set more than three follow-up emails. Keep a healthy interval between each follow-up email. 

Choose Sender Accounts

choose sender accounts on smartlead

Once done creating the email sequence, choose the email accounts you want to send from. In this case, you need 200 email accounts for sending 10,000 messages

choose multiple email accounts for sending cold emails

That’s it. You’ve launched a 10,000-leads campaign successfully. Now, sit back and check the analytics dashboard on your cold email tool. 

Final Thoughts

Sending 10,000 cold mails is no different than sending 100 messages. The practices remain the same. If anything that changes is the number of secondary domains and email accounts used for that particular campaign.

If you’re a beginner, I recommend starting small. It will help you understand cold emailing as a process and provide a chance to gain a better understanding of your target audience. 

For beginners, 10,000 might be an overwhelming volume. But, if you still want to give it a shot, go ahead.

Feel free to reach out to the Smartlead team on the Slack channel or the customer support team if you need any kind of assistance.  


How to create a lead list for cold email outreach?

To create a lead list for cold email outreach, leverage a cold email tool like Smartlead that comes with a built-in feature or integration for easy list building. Alternatively, explore databases such as, email finders like, or tools like Clay and BuiltWith. Always verify lists using tools like Usebouncer and MillionVerifier before the campaign launches.

Can you send 1,000 emails a day?

Yes, you can send 1000 emails a day with an AI-based cold email software. 

Is it legal to send cold emails?

No, sending cold emails is not illegal. However, laws and regulations like the CAN-SPAM Act and GDPR regulate cold outreach, requiring accurate information, protection of recipients' data, and application of an unsubscribe link within emails to comply with its provisions.

What’s a Rich Text element?

The rich text element allows you to create and format headings, paragraphs, blockquotes, images, and video all in one place instead of having to add and format them individually. Just double-click and easily create content.

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Static and dynamic content editing

A rich text element can be used with static or dynamic content. For static content, just drop it into any page and begin editing. For dynamic content, add a rich text field to any collection and then connect a rich text element to that field in the settings panel. Voila!

How to customize formatting for each rich text

Headings, paragraphs, blockquotes, figures, images, and figure captions can all be styled after a class is added to the rich text element using the "When inside of" nested selector system.

Author’s Details

Rajnish Das

Rajnish Das is an in-house writer at SmartWriter and SmartLead. She writes product-oriented, data-driven content for B2B SaaS audiences and educates them on marketing and sales topics. Her expertise includes outbound marketing techniques like cold emailing and LinkedIn outreach.


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Frequently asked questions

General Questions

What is Smartlead's cold email outreach software?

Email automation FAQs- Smartlead

Smartlead's cold email outreach tool helps businesses scale their outreach efforts seamlessly. With unlimited mailboxes, fully automated email warmup functionality, a multi-channel infrastructure, and a user-friendly unibox, it empowers users to manage their entire revenue cycle in one place. Whether you're looking to streamline cold email campaigns with automated email warmups, personalization fields, automated mailbox rotation, easy integrations, and spintax, improve productivity, or enhance scalability with subsequences based on lead’s intentions, automated replies, and full white-label experience, our cold email tool implifies it in a single solution.

How does the "unlimited mailboxes" feature benefit me?

Email automation FAQs- Smartlead

Our "unlimited mailboxes" feature allows you to expand your email communications without restrictions imposed by a mailbox limit. This means you won't be constrained by artificial caps on the number of mailboxes you can connect and use. This feature makes Smartlead the best cold email software and empowers you to reach a wider audience, engage with more potential customers, and manage diverse email campaigns effectively.

What do you mean by "unibox to handle your entire revenue cycle"?

Email automation FAQs- Smartlead

The "unibox" is one of the unique features of Smartlead cold email outreach tool, and it's a game-changer when it comes to managing your revenue cycle. The master inbox or the unibox consolidates all your outreach channels, responses, sales follow-ups, and conversions into one centralized, user-friendly mailbox.

With the "unibox," you gain the ability to:
1. Focus on closing deals: You can now say goodbye to the hassle of logging into multiple mailboxes to search for replies. The "unibox" streamlines your sales communication, allowing you to focus on what matters most—closing deals.

2. Centralized lead management: All your leads are managed from one central location, simplifying lead tracking and response management. This ensures you take advantage of every opportunity and efficiently engage with your prospects.

3. Maintain context: The "unibox" provides a 360-degree view of all your customer messages, allowing you to maintain context and deliver more personalized and effective responses.

How does Smartlead ensure my emails don't land in the spam folder?

Email automation FAQs- Smartlead

Smartlead, the best cold email marketing tool, ensures your emails reach the intended recipients' primary inbox rather than the spam folder. 

Here's how it works:
1. Our "unlimited warmups" feature is designed to build and maintain a healthy sending reputation for your cold email outreach. Instead of sending a large volume of emails all at once, which can trigger spam filters, we gradually ramp up your sending volume. This gradual approach, combined with positive email interactions, helps boost your email deliverability rates.

2. We deploy high-deliverability IP servers specific to each campaign. 

3. The ‘Warmup’ feature replicates humanized email sending patterns, spintax, and smart replies.
4. By establishing a positive sender reputation and gradually increasing the number of sent emails, Smartlead minimizes the risk of your emails being flagged as spam. This way, you can be confident that your messages will consistently land in the primary inbox, increasing the likelihood of engagement and successful communication with your recipients.

Can I integrate Smartlead with other tools I'm using?

Email automation FAQs- Smartlead

Certainly, Smartlead is designed for seamless integration with a wide range of tools and platforms. Smartlead offers integration with HubSpot, Salesforce, Pipedrive, Clay, Listkit, and more. You can leverage webhooks and APIs to integrate the tools you use. Try Now!

Email automation FAQs- Smartlead

What type of businesses sees the most success with Smartlead?

No, there are no limitations on the number of channels you can utilize with Smartlead. Our multi-channel infrastructure is designed to be limitless, allowing you to reach potential customers through multiple avenues without constraints.

This flexibility empowers you to diversify your cold email outreach efforts, connect with your audience through various communication channels, and increase your chances of conversion. Whether email, social media, SMS, or other communication methods, Smartlead's multi-channel capabilities ensure you can choose the channels that best align with your outreach strategy and business goals. This way, you can engage with your prospects effectively and maximize the impact of your email outreach.

Email automation FAQs- Smartlead

Do you provide me with lead sources?

Smartlead distinguishes itself from other cold email outreach software by focusing on limitless scalability and seamless integration. While many similar tools restrict your outreach capabilities, Smartlead offers a different approach.

Here's what makes us uniquely the best cold email software:

1. Unlimited Mailboxes: In contrast to platforms that limit mailbox usage, Smartlead provides unlimited mailboxes. This means you can expand your outreach without any arbitrary constraints.

2. Unique IP Servers: Smartlead offers unique IP servers for every campaign it sends out. 

3. Sender Reputation Protection: Smartlead protects your sender reputation by auto-moving emails from spam folders to the primary inbox. This tool uses unique identifiers to cloak all warmup emails from being recognized by automation parsers. 

4. Automated Warmup: Smartlead’s warmup functionality enhances your sender reputation and improves email deliverability by maintaining humanized email sending patterns and ramping up the sending volume. 

5. Multi-Channel Emphasis: Smartlead places a strong emphasis on multi-channel outreach. You can reach your prospects where they are with the LinkedIn outreach feature.   With Smartlead’s cold email automation software, you're always one step ahead in your outreach efforts, enjoying the freedom to scale your initiatives and seamlessly integrate with other tools—all while maintaining a focus on maximizing the impact of your outreach.

Email automation FAQs- Smartlead

How secure is my data with Smartlead?

Ensuring the security of your data is Smartlead's utmost priority. We implement robust encryption methods and stringent security measures to guarantee the continuous protection of your information. Your data's safety is paramount to us, and we are always dedicated to upholding the highest standards of security.

How can I get started with Smartlead?

Email automation FAQs- Smartlead

Getting started with Smartlead is straightforward! Just head over to our sign-up page and follow our easy step-by-step guide. If you ever have any questions or need assistance, our round-the-clock support team is ready to help, standing by to provide you with any assistance you may require. Sign Up Now!

How can I reach the Smartlead team?

Email automation FAQs- Smartlead

We're here to assist you! You can easily get in touch with our dedicated support team on chat. We strive to provide a response within 24 hours to address any inquiries or concerns you may have.

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