How many emails can I send per inbox per day?

2 to 5 emails per inbox per day is the safe range that protects your domain reputation and keeps deliverability high. With 300+ inboxes, that gives you 600 to 1,500 cold emails daily without any inbox raising flags.

How many warm-up emails should I send?

5 warm-up emails per inbox per day is the sweet spot. Your sending tool, Instantly recommended, handles warm-up traffic automatically. Most mailboxes are fully warmed within 14 to 21 days.

Which sequencers do these mailboxes work with?

Instantly is our recommended platform where our mailboxes run perfectly. They also work on Bison and PlusVibe, where minor setup quirks are quickly resolved by our support team. We do not recommend Smartlead with our mailboxes.

Cheap Cold Email Inboxes — $20/Domain

Q: Do you sell Outlook or Google Workspace inboxes?

We provide premium Microsoft Outlook inboxes optimized for cold email deliverability. All inboxes come with free DNS setup including SPF, DKIM, and DMARC records configured correctly.

Q: How is your pricing so cheap compared to other inbox resellers?

We operate at scale with bulk-rate domain registration and automated DNS configuration. At $20 per domain per month with up to 99 mailboxes per domain, your effective per-mailbox cost can drop to around 20 cents. Most resellers charge far more per mailbox. Our price reflects efficient infrastructure, not lower quality.

[ 01 ] Pricing

One flat price. You pick the density.

Cold Email Infrastructure

$20 / domain / month

Flat per-domain pricing. Choose how many mailboxes each domain runs — same price either way.

✓ Up to 99 mailboxes per domain
✓ Free DNS setup (SPF, DKIM, DMARC)
✓ Free integration with your sender
✓ Domain warm-up handled for you
✓ Replacement mailboxes if anything breaks

Start an Order

Choose your mailbox density

Every domain costs a flat $20/month. You decide how many mailboxes run on each domain — 20, 50, or 99. Higher density means fewer domains for the same mailbox count, which lowers your total bill. We most recommend 50 mailboxes per domain — the sweet spot for deliverability and cost.

▸ Mailboxes per domain

50 mailboxes per domain — our most recommended setup, balancing deliverability and cost.

▸ Your estimate

Total mailboxes you need

Mailboxes per domain 50

Domains required 6

Monthly cost $120/mo

Minimum order is 300 mailboxes.

[ 02 ] Compatibility

Built for Instantly. Works with more.

Our mailboxes are tuned for Instantly, where they run flawlessly. They also work on Bison and PlusVibe — you may hit a few setup quirks, but our support team sorts those out fast.

Instantly

instantly.ai

Works Perfectly

Our primary platform. Mailboxes connect and send with zero friction.

Bison

emailbison.com

Works · Support Assisted

Runs well. Any setup quirks are quickly resolved by our support team.

PlusVibe

plusvibe.ai

Works · Support Assisted

Compatible. Our team helps you through any connection hiccups.

Note: Smartlead is not recommended with our mailboxes. For the best deliverability and the smoothest setup, we suggest Instantly.

[ 04 ] Why Teams Switch

Built for teams who want to cut cold email costs without cutting deliverability.

Most cold email inbox providers nickel-and-dime you with per-mailbox fees, setup charges, and premium DNS tiers. We charge one flat rate: $20 per domain per month, with up to 99 mailboxes per domain. Here's how that works — and why it matters for outbound teams running campaigns at real scale.

The most affordable cold email inbox provider on the market

At $20 per domain with up to 99 mailboxes per domain, your effective cost can land around 20 cents per mailbox — a fraction of what most resellers charge. Flat per-domain pricing means no per-seat licensing, no surprise fees, and the more mailboxes you run per domain, the lower your total bill.

Premium Outlook inboxes, configured correctly

We provision Microsoft Outlook inboxes optimized specifically for cold email. Every inbox ships with full DNS configuration — SPF, DKIM, and DMARC records set up by us before delivery. No ticket queues, no broken authentication, no inboxes landing in spam on day one.

True reseller pricing on bulk inboxes

Our minimum order of 300 inboxes is built for cold email agencies, lead gen teams, and outbound operators who need volume. Reseller-friendly bulk pricing means the more inboxes you need, the more you save compared to per-seat licensing from major providers.

Tuned for Instantly, compatible with more

Our mailboxes are built to run flawlessly on Instantly — the platform most serious cold email teams trust. They also work on Bison and PlusVibe, and if you hit any setup quirks there, our support team resolves them fast. We don't recommend Smartlead with our mailboxes.

Cut your cold email infrastructure cost by up to 75%

Most outbound teams spend $1,000+ per month on inbox infrastructure alone. Switching to 12centsinboxs typically reduces that line item by 70 to 80 percent — money you can redirect into copywriting, list quality, or hiring an SDR. Same volume, smaller bill.

Free DNS setup. Always. No upsells.

Other inbox resellers charge a setup fee per domain, then another fee per mailbox, then a "premium DNS" tier. We don't. The flat $20 per domain covers everything: the domain, all its mailboxes, full DNS records, OAuth integration, and ongoing support. One number, no surprises.

[ 06 ] FAQ

Questions worth answering up front.

2–5 emails per inbox per day. This is the safe range that keeps deliverability high and protects your domain reputation. Going beyond that is where senders start hitting spam folders. With 300+ inboxes, you've got plenty of headroom — that's 600–1,500 cold emails daily without any single inbox raising flags.

5 warm-up emails per inbox per day is the sweet spot. We configure this automatically when we hand off your mailboxes — your sending tool (Instantly is what we recommend) handles the warm-up traffic in the background while you focus on campaigns. Most mailboxes are fully warmed and ready for full sending within 14–21 days.

Instantly is our recommended platform — our mailboxes run perfectly there. They also work on Bison and PlusVibe, where you may run into minor setup quirks that our support team resolves quickly. We do not recommend Smartlead with our mailboxes. For the smoothest experience and best deliverability, go with Instantly.

We provide premium Microsoft Outlook inboxes optimized specifically for cold email deliverability. All inboxes come with free DNS setup including SPF, DKIM, and DMARC records configured correctly out of the box. Outlook inboxes consistently outperform Google Workspace for cold outbound at this price point — better inbox placement, fewer reputation issues, and far cheaper than Workspace seat licensing.

We operate at scale with bulk-rate domain registration and fully automated DNS configuration. At a flat $20 per domain with up to 99 mailboxes per domain, your effective per-mailbox cost can drop to around 20 cents — far below what most resellers charge per seat. The price reflects efficient infrastructure, not lower quality. Same Microsoft inboxes, same DNS quality, same deliverability — just without the reseller markup.

Cold email inboxes from $0.50 $0.20 a mailbox per month.