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Cold Email Masterclass

Chapter 3 of 15

TABLE OF CONTENTS

Why Cold Email Still Works in 2026

The Cold Email Mindset Shift

3

Building Your Foundation

4

Inbox Warm-Up Strategy

5

List Building & Research

6

Writing Cold Emails That Get Replies

7

Personalization at Scale

8

Follow-Up Sequences That Convert

9

Cold Email Deliverability Mastery

10

Multi-Channel Outreach

11

AI-Powered Cold Email in 2026

12

Measuring Cold Email Performance

13

Compliance and Legal Requirements

14

Scaling Your Cold Email Operation

15

Advanced Strategies Most People Never Try

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Chapter 3

Free Masterclass

Building Your Foundation

This chapter is not exciting.

It is the most important chapter in this entire cold email masterclass.

Deliverability Is Everything

Deliverability is the foundation of everything. If your emails do not reach the inbox, your copywriting skills, your personalization, and your follow-up sequences are worthless.

The global average inbox placement rate sits at 83.1%. That means roughly 17% of all emails never reach the primary inbox. For cold email specifically, that number is worse because cold senders face higher scrutiny from spam filters.

Here is what you need to set up before sending a single cold email.

Domain Authentication: SPF, DKIM, and DMARC

These three protocols prove to email providers that you are who you say you are. Without them, your emails look suspicious.

SPF (Sender Policy Framework)

SPF tells receiving servers which IP addresses can send email on behalf of your domain. Think of it as a guest list. If the sending server is not on the list, the email gets flagged.

How to set it up: Add a TXT record to your DNS that lists your authorized sending services.

v=spf1 include:_spf.google.com include:youremailservice.com ~all

DKIM (DomainKeys Identified Mail)

DKIM adds a digital signature to each email you send. The receiving server checks this signature against a public key in your DNS. If the signature matches, the email passes verification.

How to set it up: Your email service provider generates a DKIM key pair. You add the public key as a TXT record in your DNS.

DMARC (Domain-based Message Authentication, Reporting, and Conformance)

DMARC ties SPF and DKIM together. It tells receiving servers what to do with emails that fail authentication checks.

How to set it up: Add a TXT record to your DNS.

v=DMARC1; p=reject; rua=mailto:dmarc@yourdomain.com

2026 Standard

In 2026, setting your DMARC policy to p=reject is becoming the standard. This tells receiving servers to reject any email that fails SPF or DKIM checks. It protects your domain from spoofing and signals that you take authentication seriously.

Protocol Comparison

Protocol
What It Does
Impact on Deliverability
SPF
Authorizes sending servers
✓ Prevents spoofing from unauthorized IPs
DKIM
Signs emails cryptographically
✓ Proves email was not altered in transit
DMARC
Enforces SPF + DKIM policies
✓ Tells providers how to handle failures
No Auth
Nothing
✗ Emails land in spam or get rejected

Buying Secondary Domains

Never send cold email from your primary business domain. Never.

If your company is acme.com, buy domains like getacme.com, acmehq.com, tryacme.com, or acme.io for cold outreach. If a cold email domain gets blacklisted, your primary domain stays clean. Your marketing emails, transactional emails, and customer communications remain unaffected.

Buy 3-5 secondary domains. Set up separate Google Workspace or Microsoft 365 accounts on each. Authenticate SPF, DKIM, and DMARC on every single one.

Cost: roughly $12 per domain per year plus $6-$7 per inbox per month on Google Workspace. A small price compared to having your main domain flagged as spam.

Email Provider Selection

Google Workspace and Microsoft 365 are the two dominant choices for cold email.

Google Workspace

Has the best deliverability for cold email in 2026. Google knows its own spam filters, and emails from Google Workspace tend to perform better in Gmail inboxes, which represent roughly 30% of business email.

Microsoft 365

Works well for reaching Outlook and corporate inboxes. Many enterprise companies run on Microsoft infrastructure, and emails from Microsoft 365 accounts sometimes get preferential treatment in those environments.

Strategy

The smart move: use both. Set up inboxes on Google Workspace and Microsoft 365. Rotate between them to spread volume and reduce risk.

Inbox Limits and Safe Sending

Each inbox has a safe daily sending limit for cold email:

Phase
Cold Email Sends
Time Period
New inboxes
5-10 emails per day
First 2 weeks
Warming phase
15-25 emails per day
Weeks 2-4
Fully warmed
35-50 emails per day maximum
Month 2+

These numbers feel low. That is the point. Cold email in 2026 is a precision game, not a volume game.

If you need to send 500 emails per day, you need 10-15 warmed inboxes. Not one inbox pushing 500 sends.

Firstsales.io Advantage

Tools like Firstsales.io let you connect unlimited email accounts and rotate sends automatically. This spreads volume across inboxes so no single account gets flagged for unusual activity.

Key Takeaway

Deliverability is the foundation. Skip authentication and proper setup, and nothing else matters. Set up SPF, DKIM, and DMARC. Use secondary domains. Respect inbox limits. Your future self will thank you.

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Frequently Asked Questions

Everything You Need to Know
About Cold Email in 2026

Quick answers to the most common cold email questions. From deliverability to scaling, we've got you covered.

Start with 5-10 per inbox per day for new accounts. After 2-3 weeks of warm-up, scale to 35-50 per inbox. If you need to send 500+ emails per day, use 10-15 warmed inboxes and rotate sends across all of them. Never push a single inbox beyond 50 cold emails per day.

The average reply rate across all cold campaigns is 3.43%. A 'good' reply rate is 3-8%. Top performers consistently hit 8-15%. Rates above 15% are possible with excellent targeting and trigger-based personalization but are not typical at scale.

Keep cold emails between 50-125 words. Some studies suggest up to 150 words for certain B2B audiences. Shorter emails consistently outperform longer ones. If you need more than 125 words to make your point, your message is not focused enough.

Plain text. Always. HTML emails with logos, images, and formatted layouts trigger spam filters and look like marketing emails. A plain text email from one person to another is what cold email should look like. The only exception is your email signature, which can include basic formatting.

4-7 follow-ups is the sweet spot. 42% of replies come from follow-ups rather than the first email. Space them at Day 3, Day 7, Day 14, Day 21, and Day 30. Each follow-up should add new value, not just 'bump' the thread.

Tuesday, Wednesday, and Thursday are the best days. Best times are 8-10 AM and 2-4 PM in the recipient's timezone. Avoid Monday mornings and Friday afternoons. Wednesday tends to show the highest engagement across most studies.

Yes. Sending cold email from a new inbox without warm-up will land you in spam immediately. Warm-up takes 14-21 days minimum. Keep warm-up running alongside your cold campaigns permanently. Tools like Firstsales.io include warm-up for free with all plans.

Inbox placement rate measures the percentage of emails that land in the primary inbox versus spam or tabs. The global average is 83.1%. This is different from delivery rate (98.16%), which only measures whether the server accepted the email. An email can be 'delivered' but still land in spam.

Set up SPF, DKIM, and DMARC authentication on your domain. Use secondary domains for cold outreach. Warm up new inboxes for 14-21 days. Keep bounce rates under 2%. Verify your email list before sending. Avoid spam trigger words. Send plain text emails. Keep volume consistent.

Yes, in most jurisdictions when done correctly. In the US, CAN-SPAM allows cold B2B email with proper identification and opt-out mechanisms. In the EU, GDPR allows B2B outreach under legitimate interest. In Canada, CASL requires express or implied consent. Always include your business address and an unsubscribe option.

Cold email targets a specific person with a relevant, personalized message and includes identification and unsubscribe options. Spam is unsolicited bulk email sent to purchased lists without personalization or proper opt-out mechanisms. The difference is intent, targeting, and compliance.

Cold email typically costs $30-$50 per lead, making it one of the most cost-effective B2B channels. This includes tool costs ($28-$269/month for a platform like Firstsales.io), data costs ($49-$500/month), and infrastructure costs ($150-$200/month for domains and inboxes).

No. Purchased lists contain invalid addresses, spam traps, and unverified contacts. Bounce rates skyrocket when using purchased lists, which damages your sender reputation. Build your list through research, networking, and organic lead generation instead.

Keep subject lines to 1-5 words for mobile or 6-10 words for desktop. Use lowercase. Include the company name or a trigger event when possible. Avoid spam trigger words like 'free,' 'guarantee,' or 'limited time.' Question-based and trigger-based subject lines consistently get the highest open rates.

DMARC (Domain-based Message Authentication, Reporting, and Conformance) is an email authentication protocol that ties SPF and DKIM together. Yes, you need it. Set your DMARC policy to p=reject, which tells receiving servers to reject emails that fail authentication. This protects your domain and improves deliverability.

Track reply rate (most important), positive reply rate, meeting book rate, bounce rate, and spam complaint rate. A good reply rate is 3-8%. Keep bounce rate under 2% and spam complaints under 0.1%. Measure pipeline generated monthly to connect email activity to revenue.

AI can draft cold emails, but human review is required. AI excels at research, first drafts, and timing. Humans excel at judgment, tone, and nuance. The best approach is a hybrid: AI researches and drafts, human reviews and approves. Fully automated AI emails tend to sound generic and perform worse than human-reviewed AI drafts.

It depends on your needs and budget. Firstsales.io offers the best value with plans starting at $28 per month, unlimited email accounts, free warm-up, and free list cleaning. Instantly.ai works for high-volume senders but costs more ($97-$358/mo). Apollo.io combines data and sending but limits features at lower tiers.

Add inboxes, not volume per inbox. Each inbox should send 35-50 emails per day maximum. Use 3-4 inboxes per secondary domain. Keep warm-up running permanently. Verify every list before sending. Monitor bounce rates and spam complaints daily. Scale gradually, adding 5-10 sends per day per inbox.

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COMPANY

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MASTERCLASS

All ChaptersWhy Cold Email Still WorksCold Email Mindset ShiftBuilding Your FoundationInbox Warm-Up StrategyList Building & ResearchWriting Cold Emails That Get RepliesPersonalization at ScaleFollow-Up Sequences That ConvertCold Email Deliverability MasteryMulti-Channel OutreachAI-Powered Cold Email in 2026Measuring Cold Email PerformanceCompliance and Legal RequirementsScaling Your Cold Email OperationAdvanced Strategies Most People Never Try

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