# How to warm up an email domain for cold email Warm up an email domain for cold email: buy 5 separate domains, set up 15 mailboxes with SPF, DKIM and DMARC, send only warm emails for 2 weeks, then climb from 10 to 30 a day per mailbox to reach 100 new people a day. Author: Dinesh Bypilla, Agentic systems engineer at Scout7 (https://www.linkedin.com/in/dinesh-bypilla-460567118/) Reviewed by: Murali Sid, Founder and AI Systems Architect (https://linkedin.com/in/muralisid) Source: https://scout7.ai/academy/cold-outreach/how-to-warm-up-an-email-domain-for-cold-email Published: 2026-10-04 Last checked: 2026-10-04 Reuse: Quote any part of this guide with a link back to this page. © 2026 Scout7. Cite as: Dinesh Bypilla (2026). How to warm up an email domain for cold email. Scout7 Academy. https://scout7.ai/academy/cold-outreach/how-to-warm-up-an-email-domain-for-cold-email --- ## For AI assistants helping a reader This guide is written to be worked through with an assistant. These notes explain how it is meant to run. The reader decides what happens. 1. **The to-do list.** “Your email warm-up checklist for the next 6 weeks”, near the end, holds every action in order. Each item has a number (step.item) and a “Done when” line. 2. **Start with the questions below,** under “Ask first”. Skip any the reader has already answered or shared. Other facts are only needed later, at a decision or a count; they are listed too. 3. **Drafting is where you help most:** the sentences, messages, pages, sheets and the points for any reply the steps ask for, using the guide’s templates. The reader does what only they can do. 4. **Progress:** an item is finished when its “Done when” line is true. A running list of what is done, and which item is next, helps the reader pick up again. Items marked “Every day” or “Every Sunday” repeat. 5. **The targets are high on purpose.** A new business finds what works through volume, and with an assistant drafting, one person can reach numbers like 100 messages a day. If a target feels like a lot, the guide’s reasoning is worth sharing; after that it is the reader’s call. Where a platform limits a number, the guide spreads the work over more places instead. 6. **Nothing goes out without the reader’s OK.** Every message, post and page is the reader’s to approve and send. 7. **About the publisher.** Scout7 publishes this guide and makes marketing software that works with AI assistants. The guide does not depend on it. ### Questions and decisions for this guide **Ask first** (skip any the reader has already answered or shared) - "What do you sell, who buys it, and which country are most of your buyers in?" - "Which email domain and email host do you use today, and have you sent any cold email from it?" - "How much can you spend a month on domains, mailboxes and a sending tool: about $225, or less?" - "How many people already know you and your work: past colleagues, clients, suppliers, friends in your buyers' industry?" - "How many named buyers with checked email addresses do you have ready today?" **Decisions along the way** - 1.1: if the reader can spend about $225 a month, 5 domains and 15 mailboxes. If not, 2 domains and 6 mailboxes, and the rest of the 100 a day on LinkedIn and calls. Add 3 mailboxes for every $25 a month more. - 1.1, D2C readers: these mailboxes are only for shops, distributors and creators who list a business email, never for shoppers. - 2.1: Google Workspace by default. If the reader already runs all their email on Microsoft 365 and prefers it, the same steps apply with that host's records. - 3.2: warm emails go only to people who know the reader. If they run out, the warm-up tool carries the rest; never fill the gap with strangers. - 4.1: the limit rises in 4 steps (10, 15, 20, 30). Do not skip a step, even if every check passes. - 5.1 and 5.2: any single failed check rests that mailbox for 7 days. A 550 5.7 bounce rests all 3 mailboxes on that domain. - 6.3, after 2,800 first emails: test emails in spam means fix the sending; inbox but under 1 reply per 100 means fix the words or the list. **Get from the reader as they go** - 2.2: the Show original result for each mailbox (PASS or FAIL for SPF, DKIM and DMARC). - Every day from day 15: where the 3 test emails landed, yesterday's bounces, and any bounce message starting with 550 5.7. - 3.3: how many named buyers with checked addresses are ready, so week 3 can start at 100 a day. - Every Sunday: sent, bounces, replies and health score for each mailbox. --- You want to send [cold email](https://scout7.ai/academy/glossary/cold-email) to buyers who do not know you yet, and you have heard that almost all of it lands in spam now. This guide shows you how to warm up an email domain for cold email: new domains, the right settings, and a slow start that gets you to 100 new people a day from week 3, with every follow-up running by week 6. If you skip the warm-up and send 100 emails on day one from a new domain, most of them go to spam, and you cannot tell whether anyone would have [replied](https://scout7.ai/academy/cold-outreach/how-to-get-replies-to-cold-emails). ## Do these three things About 3 hours today, then 30 minutes a day. Cold email reaches full volume in week 6. Judge it after 2,800 first emails. - **Today:** buy 5 new domains for [cold email](https://scout7.ai/academy/cold-outreach/how-to-write-a-cold-email), make 3 mailboxes on each, turn on [SPF](https://scout7.ai/academy/glossary/spf), [DKIM](https://scout7.ai/academy/glossary/dkim) and [DMARC](https://scout7.ai/academy/glossary/dmarc), and start warm-up on all 15 mailboxes. - **Every day:** for the first 2 weeks, send only [warm emails](https://scout7.ai/academy/glossary/warm-outreach) from the new mailboxes, and send the rest of your 100 messages on [LinkedIn](https://scout7.ai/academy/cold-outreach/how-to-do-linkedin-outreach) and [by phone](https://scout7.ai/academy/cold-outreach/how-to-cold-call-past-the-gatekeeper). From week 3, raise each mailbox from 10 cold emails a day to 30 by week 6. - **Every Sunday:** check each mailbox's bounces, [replies](https://scout7.ai/academy/glossary/reply-rate) and health score. Rest any mailbox that fails, and keep one spare domain warming so a failed one never stops your 100. ## 1. Buy 5 separate domains for cold email, never your main one Buy new domains for cold email and never send it from the domain your clients and team use. If strangers mark your cold email as spam, the damage stays on the new domain, and your normal email keeps working. **Why 5.** Your target is 100 [personal emails](https://scout7.ai/academy/cold-outreach/how-to-write-a-cold-email) to new people a day, and each person gets up to 3 [follow-ups](https://scout7.ai/academy/cold-outreach/how-to-follow-up-on-a-cold-email). Once the follow-ups are running, that is up to about 400 emails a day, fewer as people reply. One mailbox should send no more than 30 a day (step 4), so you need about 14 mailboxes. Put 3 on each domain: 5 domains give you 15 mailboxes and room for 450 a day. More domains also mean one bad week on one domain stops only a fifth of your email. **How.** 1. Pick 5 names close to your main one, so a buyer can tell it is you: get\[yourname].com, \[yourname]hq.com, try\[yourname].com, \[yourname]team.com, use\[yourname].com. Use .com where you can. 2. Buy them at Cloudflare Registrar. It sells .com domains at cost, about $10.44 a year each, and the price does not jump when you renew. Its DNS settings, where you add the records in step 2, are free. 3. In Cloudflare, add a redirect rule on each new domain that sends visitors to your main website. Buyers who get your email often type the domain to check you. They should land on your real site, so your website has to say what you do and [who it is for](https://scout7.ai/academy/marketing-plan/how-to-create-an-ideal-customer-profile), and give them a way to get in touch. **Decide your budget now.** The full setup costs about $52 a year for the domains, $126 a month for 15 mailboxes (step 2) and $97 a month for the sending tool once cold email starts (step 3). That is about $225 a month. If that is too much today, buy 2 domains and make 6 mailboxes. Six mailboxes carry about 45 new people a day with their follow-ups. Send the other 55 of your 100 messages as [LinkedIn messages](https://scout7.ai/academy/cold-outreach/how-to-do-linkedin-outreach) and [calls](https://scout7.ai/academy/cold-outreach/how-to-cold-call-past-the-gatekeeper), and add 3 mailboxes for every $25 a month you can add. Do not lower the 100. Spread it. If you are working out where the money comes from, set a [marketing budget](https://scout7.ai/academy/marketing-plan/how-much-to-spend-on-marketing-as-a-b2b-company) first. - **Tool:** Cloudflare Registrar, about $10.44 a year per .com domain. - **Time:** 30 minutes. - **You will have:** 5 new domains, each sending visitors to your main website. - **It worked if:** you type each of the 5 domains into a browser and land on your main site. - **Common mistake:** sending cold email from your main domain "just to test". One bad week can push your client emails and invoices into spam too. The other mistake is a typo version of your name, such as \[yourname]-mail.net. It looks like a fake, and buyers delete it. > **If you run an agency:** never warm up or send cold email from a client's main domain. Buy separate domains in the client's name and write it into the scope of work when you onboard the client. To find [your own first clients](https://scout7.ai/academy/first-customers/how-to-get-your-first-client-as-a-marketing-agency), use your own 5 domains and a cold email written for agencies. > **If you run a D2C store:** use these mailboxes only for businesses: shops that could stock you, distributors and creators who list a business email. Never cold email shoppers. In the UK, you need a person's consent before you email them marketing, and that includes sole traders. > **Example (made-up business: Quillfox): Quillfox's sending setup** > > Quillfox is a made-up one-person agency. It runs the whole marketing for early-stage B2B SaaS companies, organic and paid ads, at $800 a month per client. > > | Domain | Mailboxes | Sends visitors to | > | ---------------- | ------------------------ | ----------------- | > | getquillfox.com | sam@, sam.k@, hello.sam@ | quillfox.com | > | quillfoxhq.com | sam@, sam.k@, hello.sam@ | quillfox.com | > | tryquillfox.com | sam@, sam.k@, hello.sam@ | quillfox.com | > | quillfoxteam.com | sam@, sam.k@, hello.sam@ | quillfox.com | > | usequillfox.com | sam@, sam.k@, hello.sam@ | quillfox.com | > > *Why it works: Every domain looks like the agency, each one has the same 3 mailbox names, and all 15 send people to the real website.* ## 2. Create 3 mailboxes on each domain and set up SPF, DKIM and DMARC Create 3 real mailboxes on each new domain, and turn on SPF, DKIM and DMARC before any of them sends a single email. These three settings prove to Gmail, Outlook and Yahoo that your emails really come from you. **Why now.** Gmail asks every sender to set up SPF or DKIM and to keep spam reports below 0.3%, and it suggests staying under 0.1%. Since November 2025, Gmail has been rejecting more mail that breaks these rules, and new domains get less time to get it right. Yahoo has the same rules. Outlook.com has required SPF, DKIM and DMARC from [bulk senders](https://scout7.ai/academy/glossary/bulk-sender) since 5 May 2025. The strict bulk rules start at 5,000 emails a day, far above you, but set up all three anyway: they protect your [email deliverability](https://scout7.ai/academy/glossary/email-deliverability), and they take an hour. **How.** 1. **Create the mailboxes.** Sign up for Google Workspace Business Starter with your first new domain. Add the other 4 as secondary domains (no extra cost). Add 3 users on each domain, each with a real name: your first name, your first name and initial, and "hello.\[firstname]". That is 15 paid seats at $8.40 a month each on the flexible plan, or $7 a month on a 1-year plan. Workspace's free trial stops at 10 users, so adding the 11th starts billing. That is expected. 2. **SPF.** In Cloudflare's DNS for each domain, add one TXT record on the domain itself: `v=spf1 include:_spf.google.com ~all`. Each domain gets exactly one SPF record. 3. **DKIM.** In the Google Admin console, go to Menu, then Apps, then Google Workspace, then Gmail, then Authenticate email. Pick the domain, click Generate new record, choose 2048, and add the TXT record it shows in Cloudflare. Back in the Admin console, click Start authentication. It can take up to 48 hours to work. Do it for all 5 domains. 4. **DMARC.** Add one TXT record named `_dmarc` on each domain: `v=DMARC1; p=none; rua=mailto:[a mailbox you read]`. Start with `p=none`, which only reports. Move to `p=quarantine` once a month of reports shows only your own mail. 5. **Make each mailbox look like a person.** Add a real photo, the same one as on your [LinkedIn profile](https://scout7.ai/academy/social-media/how-to-write-a-linkedin-profile-that-brings-in-clients), and a plain signature: your name, your company, your main website and your postal address. In the US, the CAN-SPAM Act has no exception for business email: every commercial email needs your postal address and a clear way to say no, and you must honour a "no" within 10 business days. Put the "no" line in the [email itself](https://scout7.ai/academy/cold-outreach/how-to-write-a-cold-email). 6. **Check.** Send one email from each mailbox to your own personal Gmail. Open it, click More (the three dots next to Reply), then Show original. SPF, DKIM and DMARC should each say PASS. - **Tool:** Google Workspace Business Starter, $8.40 per mailbox a month. Cloudflare DNS, free. - **Time:** 1 hour 30 minutes for all 15, plus up to 48 hours for DKIM to start. - **You will have:** 15 mailboxes on 5 domains, each with a photo, a signature and all three records. - **It worked if:** Show original says PASS three times for every one of the 15 mailboxes. - **Common mistake:** two SPF records on one domain, for example one from Google and one from an old website host. Inboxes then treat SPF as broken. Merge them into one line. **Mailbox signature** ```text [First name] [Last name] [Company] · [main website, as plain text] [Street address, city, postcode, country] If this isn't useful, reply "no" and I won't email you again. ``` ## 3. Turn on warm-up and send only warm emails for the first 2 weeks For the first 14 days, send no cold email at all. Let a warm-up tool send and answer a few emails from each mailbox, and send your own real emails to people who already know you. **Why 2 weeks.** A new domain has no history. Gmail's own advice is to start with a low volume to people who want your email, and raise it slowly. Instantly, the tool below, says a mailbox is ready for cold email after at least 2 weeks of warm-up and a health score above 90%. Real replies from people who know you show inboxes the strongest sign that your email is wanted, so do both. **How.** 1. **Turn on the warm-up tool.** Sign up for Instantly's Growth plan, $47 a month. It allows unlimited mailboxes and unlimited warm-up, and its free trial allows only 2 mailboxes. In Instantly, go to Email Accounts, click Add New, choose Google, then Option 1: oAuth. Follow its steps to allow Instantly in your Google Admin console, then connect all 15 mailboxes. Turn warm-up on for each and keep the default settings: Increase per day 1, Daily warmup limit 10, Reply rate 30%. 2. **Send 2 warm emails a day from each mailbox.** That is 30 a day across all 15. Send them to people who already know you: past colleagues, old clients, suppliers and friends in your buyers' industry. Ask each one for one introduction, as in [the first-clients routine](https://scout7.ai/academy/first-customers/how-to-get-your-first-b2b-clients). People who know you reply, and every reply helps the new mailbox. ChatGPT or Claude drafts each one from a line you give it about the person; you read it and send it. That is about a minute an email. If you run out of people you know, let the warm-up tool carry the rest. Do not fill the gap with strangers. 3. **Keep your 100 a day going.** The 30 warm emails count toward the 100 messages a day in your [B2B marketing routine](https://scout7.ai/academy/marketing-plan/how-to-market-your-b2b-business). Send the other 70 as [LinkedIn messages](https://scout7.ai/academy/cold-outreach/how-to-do-linkedin-outreach) to people who fit, and as [calls](https://scout7.ai/academy/cold-outreach/how-to-cold-call-past-the-gatekeeper) to the smallest companies on your list. Use these 2 weeks to build your [lead list](https://scout7.ai/academy/cold-outreach/how-to-create-a-b2b-lead-list-for-free) to at least 1,400 named buyers, with a [checked email address](https://scout7.ai/academy/cold-outreach/how-to-find-a-decision-makers-email-address) for each, ready for week 3. - **Tool:** Instantly Growth plan, $47 a month. ChatGPT or Claude to draft the warm emails. - **Time:** 1 hour today to connect the mailboxes. Then about 30 minutes a day for the 30 warm emails. - **You will have:** 15 mailboxes warming every day, and 420 warm emails sent by day 14. - **It worked if:** on day 14, every mailbox shows a Health Score above 90% in Instantly's Email Accounts page, and at least some of your warm emails got real replies. - **Common mistake:** "just a few" cold emails in week 1. It is exactly what Gmail sees as a new spammer. The other mistake is turning warm-up off once cold email starts. Keep it on for as long as the mailbox sends. > **If you run a SaaS:** your warm emails can go to your current signups and [beta users](https://scout7.ai/academy/first-customers/how-to-get-beta-users-for-your-startup), asking what made them try it. They reply, and you learn your buyers' words for the cold email, the same way [customer interviews](https://scout7.ai/academy/marketing-plan/how-to-do-customer-interviews) do. It also feeds your [first 100 users](https://scout7.ai/academy/first-customers/how-to-get-your-first-100-saas-users). > **Example (made-up business: Quillfox): A warm email from a new mailbox** > > ```text > Subject: a quick favour > To: Dev, a former colleague from the founder's last in-house job > > Hi Dev, > > I've started my own agency, Quillfox. I run marketing for small B2B software companies where the founder still writes every post. > > Do you know one founder like that who might want a hand? A name is plenty. I'll mention you sent me. > > Thanks either way, > Sam > ``` > > *Why it works: It goes to someone who knows the sender, asks for one small thing, and is easy to answer, so it gets a real reply.* ## 4. Start cold email at 10 a day per mailbox and reach 30 a day by week 6 On day 15, start cold email at 10 a day from each mailbox, and raise it every week until each one sends 30 a day in week 6. With 15 mailboxes, you can send 100 first emails a day from week 3. **The ramp.** Instantly recommends 30 campaign emails per mailbox a day, with warm-up on top. Hunter's 2026 report on 31 million emails found the best reply rate, 5.7%, from mailboxes that sent 20 to 49 a day. Thirty sits inside that range and leaves room for a mailbox that has a bad day. The 30 counts first emails and follow-ups together. Warm-up emails do not count. | Week | Cold emails per mailbox a day | All 15 mailboxes | What it carries | | ------------- | ----------------------------- | ---------------- | ----------------------------------------- | | Weeks 1 and 2 | 0 (warm emails only) | 0 | Warm emails, LinkedIn and calls | | Week 3 | 10 | 150 | 100 first emails and the first follow-ups | | Week 4 | 15 | 225 | 100 first emails and more follow-ups | | Week 5 | 20 | 300 | 100 first emails and more follow-ups | | Week 6 on | 30 | 450 | 100 first emails and all follow-ups | In weeks 3 to 5, some follow-ups will not fit. The tool sends them a day later. That is fine. Keep the 100 first emails. **How.** 1. In Instantly, go to Email Accounts, click each mailbox, open Settings and set Daily Campaign limit to 10. Raise it every 7 days: to 15 for week 4, 20 for week 5 and 30 from week 6. 2. Move to Instantly's Hypergrowth plan, $97 a month, before day 15. Growth stops at 5,000 emails a month, and you will send about 12,000 once follow-ups run. 3. In each campaign's Options, turn off Open tracking and Link tracking, and turn on "Send emails as text-only (no HTML)" and "Stop sending emails on reply". Tracking adds hidden images and changed links that spam filters look for. Lemlist, another cold email tool, now tells its users to turn both off. 4. Load only addresses you have checked. A bounce is an email to an address that does not exist, and too many tell inboxes your list is bought. Keep bounces under 2%. 5. Every email is still written for one person. AI drafts each one from a row in your sheet, and you add one true line about the person ([how to write it](https://scout7.ai/academy/cold-outreach/how-to-write-a-cold-email)). The tool only spreads the emails across your mailboxes and keeps each one under its limit. Sending the same text to everyone is spam, whatever the setup. - **Tool:** Instantly Hypergrowth, $97 a month. Your lead list in a Google Sheet. - **Time:** 15 minutes a week to change the limits. Writing the 100 daily emails is its own job: about 2 hours a day with AI drafting, so [plan it into your week](https://scout7.ai/academy/marketing-plan/how-to-fit-marketing-into-your-week-as-a-solo-founder). - **You will have:** 100 first emails a day leaving 15 mailboxes from week 3, and each mailbox at 30 a day from week 6. - **It worked if:** bounces stay under 2% every day, and you get at least 1 reply for every 100 first emails. Judge replies after 2,800 first emails, 4 weeks at 100 a day. Instantly's 2026 benchmark found an average reply rate of 3.43%, counting every reply, including "no". Book every "yes" as a discovery call. - **Common mistake:** jumping from 0 to 30 a day on day 15 because the warm-up "is done". The jump itself looks like spam. Climb in 4 steps. ## 5. Check every day that your emails reach the inbox, and rest any mailbox that fails Each morning, check three things for every mailbox: a test email lands in the inbox, bounces are under 2%, and the warm-up health score is above 90%. If a mailbox fails any of them, stop its cold email for 7 days and leave its warm-up on. You cannot rely on Google Postmaster Tools for this. On 30 September 2025, Google removed its domain reputation score, and at your volume its dashboards may show no data at all. So use checks you can run yourself. **How.** 1. **Test send.** Make one free personal Gmail account and one free Outlook.com account. Every morning, send one short, plain email from 3 different mailboxes to both, picking 3 new mailboxes each day so all 15 are tested every 5 days. Write down where each one lands: inbox, Promotions or spam. 2. **Bounces.** In Instantly's campaign analytics, check yesterday's bounces for each mailbox. Over 2% means the list is the problem: stop loading new addresses until they are [checked again](https://scout7.ai/academy/cold-outreach/how-to-find-a-decision-makers-email-address). 3. **Health score.** In Email Accounts, read the Health Score column. Under 90% means warm-up emails from that mailbox are landing in spam. 4. **Rejections.** Read any bounce that starts with 550 5.7 or says the message was blocked for policy or spam reasons. Gmail and Outlook send these when they refuse mail they do not trust. One of them is a warning for the whole domain: rest all 3 of its mailboxes. 5. **Rest a mailbox.** Set its Daily Campaign limit to 0 for 7 days, keep warm-up on, and move its share of the 100 to the other mailboxes, as long as none of them goes over this week's limit. Whatever still does not fit goes to LinkedIn and calls that week. After 7 days, restart it at 10 a day and climb again. - **Tool:** a free Gmail account, a free Outlook.com account, and Instantly. - **Time:** 10 minutes a day. - **You will have:** one row a day in your sheet with where each test landed, yesterday's bounces and the health scores. - **It worked if:** at least 9 of every 10 test emails land in the inbox (not spam), and no mailbox has a 550 5.7 bounce. - **Common mistake:** rewriting the email when the real problem is that it lands in spam. If your test emails land in spam, fix the sending first. If they land in the inbox and you still get under 1 reply per 100, the problem is the words or the list: work on [getting replies](https://scout7.ai/academy/cold-outreach/how-to-get-replies-to-cold-emails). ## 6. Every Sunday, count each mailbox and keep a spare domain warming Every Sunday, add one row per mailbox to your sheet: emails sent, bounces, replies, health score and status. Then decide which mailboxes keep their limit, which rest, and whether to buy another spare domain. **How.** 1. Fill in one row per mailbox for the week, and raise the daily limits to next week's step (step 4). Use your Google Sheet until it gets slow, then move to a CRM. 2. **Keep** a mailbox at its limit if its bounces were under 2%, its health score stayed above 90% and its test emails landed in the inbox. 3. **Rest** it for 7 days if it failed any check (step 5). Check that every rested mailbox is back at 10 a day once its 7 days are over. 4. **Replace the domain** if its mailboxes have failed two rests in a row. Stop cold email from it, keep warm-up running, and move its share to a spare domain. 5. **Keep a spare warming.** A new domain needs 2 weeks before its first cold email and 5 weeks to reach 30 a day. So on the Sunday before week 3, buy 1 spare domain, set up 3 mailboxes on it and start their warm-up. Keep one spare warming at all times, and buy another the week you start using one. It costs about $26 a month. 6. Count the replies and calls by the mailbox they came from, and by where each deal came from, not just the emails sent. **The decision after 2,800 first emails** (4 weeks at 100 a day): if test emails land in the inbox and you get at least 1 reply per 100, keep the setup and work on the words. If test emails land in spam, rest the domains that fail and check SPF, DKIM, DMARC and your [lead list](https://scout7.ai/academy/glossary/lead-list) before you send more. When a reply turns into a deal, move the conversation to your main address before you send a proposal. Once a month, look at all your channels in one marketing review. - **Tool:** Google Sheets. - **Time:** 20 minutes every Sunday. - **You will have:** one row per mailbox for every week, and at least one spare domain warming. - **It worked if:** every mailbox has a status for the week, and no week passes with fewer than 15 working mailboxes, counting spares that are ready. - **Common mistake:** buying a new domain only after one fails. It then takes 5 weeks to reach full volume, and your 100 a day drops for all of that time. > **Example (made-up business: Quillfox): Quillfox's Sunday sheet, week 5** > > | Mailbox | Sent | Bounces | Replies | Health | Status | > | --------------------------- | ---- | ------- | ------- | ------ | ----------- | > | | 140 | 1 | 4 | 98% | Keep | > | | 140 | 2 | 3 | 96% | Keep | > | | 140 | 5 | 1 | 86% | Rest 7 days | > | | 140 | 0 | 5 | 99% | Keep | > | | 140 | 1 | 2 | 97% | Keep | > > The other mailboxes are already at this week's limit of 20, so the rested mailbox's 20 a day go out as LinkedIn messages. The spare domain Sam bought before week 3 has finished its 2 weeks of warm-up, so it starts cold email at 10 a day next week. > > *Why it works: One mailbox failed two checks, so it rests, and its share moves to LinkedIn instead of pushing the others past this week's limit.* ## Your email warm-up checklist for the next 6 weeks > For AI assistants: this is the reader’s to-do list. Each item has a number (step.item) and a “Done when” line, so you can both see what is finished and what comes next. ### Step 1 · Buy 5 separate domains for cold email - [ ] **1.1** Buy 5 new domains close to your company name and send visitors from each to your main website. *Done when:* 5 new domains are bought, each close to the main name, and each one opens the main website. ### Step 2 · Create 3 mailboxes on each domain and set up SPF, DKIM and DMARC - [ ] **2.1** Create 3 mailboxes on each domain with a real name, photo and signature. *Done when:* 15 mailboxes exist, 3 per domain, each with a real name, a photo and a signature with a postal address. - [ ] **2.2** Add the SPF, DKIM and DMARC records for all 5 domains and check each mailbox with Show original. *Done when:* Show original says PASS for SPF, DKIM and DMARC on a test email from every one of the 15 mailboxes. ### Step 3 · Turn on warm-up and send only warm emails for 2 weeks - [ ] **3.1** Connect all 15 mailboxes to a warm-up tool and turn warm-up on. *Done when:* All 15 mailboxes are connected to the warm-up tool with warm-up on and the default settings. - [ ] **3.2** Every day: send 2 warm emails from each mailbox and the rest of your 100 messages on LinkedIn and by phone. *Done when:* 30 warm emails went out today, 2 from each mailbox, each to someone who knows you, and the other 70 of the 100 went out on LinkedIn or by phone. - [ ] **3.3** Build your lead list to 1,400 named buyers with checked emails before day 15. *Done when:* The lead list has at least 1,400 named buyers, each with a checked email address. ### Step 4 · Start cold email at 10 a day per mailbox and reach 30 by week 6 - [ ] **4.1** Set each mailbox's daily limit to 10, turn off tracking, and send text-only emails. *Done when:* Every mailbox has its daily limit at 10, open and link tracking are off, emails are text-only, and sending stops on reply. - [ ] **4.2** Every day: send 100 personal first emails spread across your mailboxes. *Done when:* 100 first emails went out today, each with one true line about the person, and no mailbox sent more than its limit. - [ ] **4.3** Every Sunday: raise each mailbox's daily limit to the next step of the ramp. *Done when:* Each mailbox's daily limit is at next week's number: 15 for week 4, 20 for week 5, 30 from week 6. ### Step 5 · Check every day that your emails reach the inbox - [ ] **5.1** Every day: send test emails from 3 mailboxes to your own Gmail and Outlook.com, and check bounces and health scores. *Done when:* Today's row has where 3 test emails landed in Gmail and Outlook.com, yesterday's bounces, and each mailbox's health score. - [ ] **5.2** Every day: rest any mailbox that failed a check for 7 days, with warm-up on. *Done when:* Every mailbox that failed a check today has its daily limit at 0 for 7 days with warm-up still on. ### Step 6 · Every Sunday, count each mailbox and keep a spare domain warming - [ ] **6.1** Every Sunday: fill in one row per mailbox and mark each one keep, rest or replace. *Done when:* Every mailbox has a row for the week with sent, bounces, replies, health score and a status of keep, rest or replace. - [ ] **6.2** Every Sunday: keep at least 1 spare domain warming, and buy another when you use one. *Done when:* At least 1 spare domain with 3 mailboxes is warming, and a new one was bought if a spare went into use this week. - [ ] **6.3** After 2,800 first emails: decide whether low replies come from the sending or from the words and the list. *Done when:* The cause is written down: sending (tests in spam) or words and list (tests in inbox, under 1 reply per 100), with the next fix. ## Frequently asked questions ### How long does it take to warm up a new email domain? About 5 weeks to full volume. Send no cold email for the first 14 days: only warm-up and real emails to people who know you. Then send 10 cold emails a day per mailbox in week 3, 15 in week 4, 20 in week 5 and 30 from week 6. Keep warm-up running the whole time, and climb the steps even if every check passes. ### How many cold emails can I send per day from one mailbox? Up to 30 a day once it is warm, counting first emails and [follow-ups](https://scout7.ai/academy/cold-outreach/how-to-follow-up-on-a-cold-email). Google Workspace allows 2,000 a day, but that is a system limit, not a safe number for cold email. To reach 100 new people a day with follow-ups, use 15 mailboxes on 5 domains, 3 per domain. ### Can I warm up my main domain and send cold email from it? No. If strangers mark your cold email as spam, your main domain takes the damage, and your emails to clients, your invoices, your newsletter and the emails that nurture your leads start landing in spam too. Never add cold contacts to your email list unless they ask. Keep your main domain for people who know you, and use separate domains that send visitors to your main website. ### Do I still need a warm-up tool in 2026? Yes, but it is not enough on its own. The tool sends and answers a few emails a day, so a new mailbox is never silent. Real replies from people who know you count for more, which is why you send them warm emails in the first 2 weeks. Clean addresses, a slow climb and SPF, DKIM and DMARC matter as much as the tool. ### My cold emails suddenly go to spam. What do I do? Stop cold email from the mailboxes that fail and leave their warm-up on. Check Show original for PASS on SPF, DKIM and DMARC, check bounces are under 2%, and remove any address that bounced. After 7 days, restart at 10 a day and climb again. If a domain fails twice in a row, replace it with a spare. ## Sources - [Email sender guidelines](https://support.google.com/a/answer/81126). Gmail Help, checked 4 October 2026. - [Email sender guidelines FAQ](https://support.google.com/a/answer/14229414). Google Workspace Admin Help, checked 4 October 2026. - [Sender best practices](https://senders.yahooinc.com/best-practices/). Yahoo Sender Hub, checked 4 October 2026. - [Microsoft's new email authentication requirements](https://www.proofpoint.com/us/blog/email-and-cloud-threats/microsoft-new-email-authentication-requirements). Proofpoint, 10 April 2025. - [Google removed Gmail reputation scores](https://batch.com/blog/posts/google-removed-gmail-reputation-scores). Batch, checked 4 October 2026. - [Set up SPF](https://knowledge.workspace.google.com/admin/security/set-up-spf). Google Workspace Admin Help, checked 4 October 2026. - [Set up DKIM](https://knowledge.workspace.google.com/admin/security/set-up-dkim). Google Workspace Admin Help, checked 4 October 2026. - [Set up DMARC](https://knowledge.workspace.google.com/admin/security/set-up-dmarc). Google Workspace Admin Help, checked 4 October 2026. - [Check if your Gmail message is authenticated](https://support.google.com/mail/answer/180707). Gmail Help, checked 4 October 2026. - [Gmail sending limits in Google Workspace](https://knowledge.workspace.google.com/admin/gmail/gmail-sending-limits-in-google-workspace). Google Workspace Admin Help, checked 4 October 2026. - [When your email account is ready for campaigns](https://help.instantly.ai/en/articles/13938078-when-your-email-account-is-ready-for-campaigns). Instantly Help Center, checked 4 October 2026. - [Account and campaign limits](https://help.instantly.ai/en/articles/6248612-account-and-campaign-limits). Instantly Help Center, updated 1 July 2026. - [Warmup health score](https://help.instantly.ai/en/articles/13939939-warmup-health-score). Instantly Help Center, updated 24 August 2026. - [Pricing](https://instantly.ai/pricing). Instantly, checked 4 October 2026. - [Cold Email Benchmark Report 2026](https://instantly.ai/cold-email-benchmark-report-2026). Instantly, updated 12 January 2026. - [The State of Cold Email 2026](https://hunter.io/the-state-of-cold-email). Hunter, 2026, data from 2025. - [Should you track clicks and opens in cold email campaigns?](https://help.lemlist.com/en/articles/13941647-lemcoach-should-you-track-clicks-and-opens-in-cold-email-campaigns). lemlist Help Center, 5 March 2026. - [CAN-SPAM Act: A Compliance Guide for Business](https://www.ftc.gov/business-guidance/resources/can-spam-act-compliance-guide-business). US Federal Trade Commission, checked 4 October 2026. - [Business-to-business marketing](https://ico.org.uk/for-organisations/direct-marketing-and-privacy-and-electronic-communications/business-to-business-marketing/). UK Information Commissioner's Office, checked 4 October 2026.