Updated: June 2026
Three years ago, launching a cold email campaign meant waiting. You'd buy domains, set up inboxes, then run "warmup" for 3-6 weeks—sending fake emails to fake addresses to convince Gmail you weren't a spammer. By the time you started real outreach, your enthusiasm (and budget) had evaporated.
That wait is now optional for IP warmup. But the way most providers talk about "no warmup" is misleading. You can't just blast 1,000 emails on day one and expect deliverability. The game has changed, not disappeared.
At ColdSend, we're dedicated to solving the infrastructure problem for agencies. Right now, that means Azure Communication Services with pre-warmed IPs. Tomorrow, it might mean other infrastructure layers—we're exploring several dimensions. But the constant is this: our sequencer is solid regardless of how you connect your inboxes. Migrating to ColdSend makes sense now because you get immediate relief on the IP side and a platform that keeps improving.
Here's how it actually works.
The Real Constraint
The old bottleneck was IP reputation. Every new sender got a fresh IP address with no history, so you had to "warm" it gradually. That's largely solved—Azure Communication Services (ACS) uses enterprise IP pools that already have trusted reputations.
The safety net: If an ACS IP ever lands on a blocklist, Microsoft replaces it automatically. If you bought your own dedicated IP and it burned, it is gone forever. With ACS, the IP risk sits with Microsoft, not you.
The new bottleneck is domain reputation. When you send from you@yourcompany.com, Gmail looks at your domain's history. New domain = unknown = suspicious. You still need to build trust, but you can do it with real emails instead of fake warmup conversations. Monitor your domain reputation with Google Postmaster Tools.
What this means practically:
- Start sending immediately on ACS (pre-warmed IPs carry you)
- Send 5 emails per inbox day one (not 200)
- Add 5 emails per inbox each week until you reach 30–50. We recommend 30.
- Your domain reputation builds through actual engagement, not artificial chitchat
The providers telling you to send 500 emails per inbox on day one are lying. The providers making you wait a month to send anything are obsolete.
BYOA vs. DFY: How to Power Your Plan
Every ColdSend plan runs on Azure Communication Services. The only question is who manages the Azure account.
BYOA (Bring Your Own Azure)
- You create the Azure account. You pay Microsoft directly (~$2/month).
- You own the tenant, the IPs, and every inbox created there.
- ColdSend automates the setup (DNS, inbox creation, monitoring) on top of your account.
- Takes about 5 minutes. Follow our setup guide.
- The cheaper option. Full infrastructure ownership.
DFY (Done For You)
- We create and manage the Azure account for you.
- No Azure portal. No Microsoft bill. No setup steps.
- It is bundled into your plan price.
- You still own the inboxes and can export them anytime — but the Azure tenant is managed by us.
- Costs $20–$100 more per month depending on the tier.
Why both exist: Some users want total control and ownership (BYOA). Others just want to send emails and never think about Azure (DFY). The toggle lets you switch between them anytime without changing tiers.
The ColdSend Playbook
We built ColdSend around a specific strategy: use ACS to fast-track domain reputation, then scale or migrate as needed. You can stay on ACS indefinitely, or you can rotate domains to other infrastructure once they have reputation.
Why ACS First?
Azure Communication Services gives you:
- Pre-warmed enterprise IP pools (90+ reputation scores out of the box)
- ~100,000 emails per month per Infra Bundle slot
- 4 domains, 100 inboxes per domain
- No IP warmup needed
You connect your own Azure account (we'll show you how—takes 5 minutes, costs ~$2/month with BYOA). Or choose DFY and we handle everything. Either way, you own the inboxes and can export them.
Month-by-Month: What Actually Happens
Week 1
- Set up Azure account (5 minutes with BYOA, instant with DFY)
- Connect to ColdSend, configure 4 domains
- DNS records auto-generated
- Start sending: 20-30 emails per inbox per day
- Check Google Postmaster daily
Week 2-3
- Ramp up by 5 emails per inbox per week as reputation builds
- Watch bounce rates (should stay under 5%)
- Reply to every response quickly (reputation signal)
Month 2
- Domains hitting "Medium" reputation in Postmaster
- Consider: stay on ACS, add more slots, or start migration?
Month 3+
- If scaling on ACS: add Infra Bundle slots to Agency ($49/mo BYOA or $99/mo DFY each)
- If migrating (risk distribution): move warmed domains to Google Workspace/Outlook, import into ColdSend
- Put new domains on ACS, repeat cycle
Scaling Strategy: Three Ways to Grow
Option A: Stay on ACS (Simplest)
Just keep adding Infra Bundle slots to your Agency plan. Each slot adds:
- 4 domains, 400 inboxes
- ~100,000 emails/month
- Pre-warmed IPs, no migration headache
Best for: Agencies who want simplicity and don't want to manage external inboxes.
Option B: Sequential Rotation (Least Risky)
- Month 1: New domains on ACS, sending 5–30 emails/day
- Month 2: Domains show "Medium" or "High" reputation in Google Postmaster
- Month 3: Move those domains to Google Workspace/Outlook, put fresh domains on ACS
- Repeat to scale indefinitely
Why this is the least risky approach: You distribute your sending across multiple infrastructure providers. If Azure ACS ever has deliverability issues, your entire operation isn't affected — only your fresh domains are on ACS while your warmed domains are on Google/Outlook. This is infrastructure diversification.
Best for: Agencies who want to distribute risk across multiple providers and avoid single-infrastructure dependency.
Option C: Parallel Track
- Run real campaigns on ACS domains (building reputation through actual sends)
- Simultaneously warm up other domains through traditional methods
- Swap when ready
Best for: Teams transitioning from another platform or testing ColdSend side-by-side.
The Downsides
This isn't magic. Three things will still get you blocked:
-
Bad lists. If you're scraping emails or buying lists, you'll hit spam traps regardless of infrastructure. ACS doesn't fix garbage data.
-
Aggressive ramping. Going from 0 to 50 emails per inbox in 48 hours looks robotic. The algorithm is watching your pattern, not just your volume.
-
No replies. If nobody responds to your emails, Gmail notices. Warmup tools used to fake this with reciprocal opens. We don't. Your copy actually has to work.
Who Should Use What
ColdSend Agency
- Price: $199/month (BYOA) or $299/month (DFY)
- What you get: 2 Infra Bundle slots (800 inboxes, 8 domains, 200K sends), all features, 10 team seats, add-on slots
- Best if: You're starting fresh, managing multiple clients, or want to scale to 1M+ emails/month with add-on slots
ColdSend Scale
- Price: $129/month (BYOA) or $179/month (DFY)
- What you get: 1 Infra Bundle slot (400 inboxes, 4 domains, 100K sends), full API + AI tools, warmup tool, 4 team seats
- Best if: You need API access, automation, and team collaboration on pre-warmed IP infrastructure
ColdSend Growth
- Price: $79/month (BYOA) or $99/month (DFY)
- What you get: 1 Infra Bundle slot (400 inboxes, 4 domains, 100K sends), full sequencer
- Best if: You're a solo sender getting started, or testing the platform before scaling up
All plans include: Unlimited imported inboxes (Google, Outlook, SMTP) on top of your Infra Bundle slots.
Bottom Line
You don't need to wait a month to start cold email. You also can't ignore reputation entirely. The middle path: start immediately on pre-warmed IPs, build domain reputation through real (conservative) sending, then scale or migrate as needed.
The warmup industry convinced everyone that waiting was mandatory. It isn't—for IPs. But the "blast 10,000 emails on day one" crowd is just as wrong. Domain reputation still matters. The truth is in the middle: start fast on good IPs, ramp smart on domains, own your infrastructure.
And if you're worried about betting on a single approach—don't. ACS is our solution today. The sequencer is the foundation. Migrate for the infrastructure, stay for the workflow.
Ready to start?
BYOA: Growth gives you pre-warmed Azure IPs for $79/mo (you bring the Azure account, ~$2/mo). Agency for 2 slots, 200K sends, and add-on capacity at $49/slot.
DFY: Growth at $99/mo, Scale at $179/mo, or Agency at $299/mo — we manage the Azure account, you just send.
Tools to help:
- Generate email variations with Spintax — avoid sending identical copy
- Compare infrastructure options — see how we stack up
