Question 1

What is Warm Inboxes?

Accepted Answer

Warm Inboxes is your trusted platform for purchasing prewarmed and regular email accounts for Google Workspace and Microsoft 365. Accounts are ready for successful email outreach with high deliverability and ease of setup.

Question 2

What are prewarmed email inboxes?

Accepted Answer

Prewarmed email inboxes are email accounts that have been gradually conditioned over time to send emails at scale without triggering spam filters. They are ready to use immediately with warm deliverability.

Question 3

Do prewarmed inboxes include domains?

Accepted Answer

Yes, a free prewarmed .COM/.CO domain is included with every prewarmed package, saving you $12+ per domain. Fresh inboxes run on domains you own or buy through us.

Question 4

How much do prewarmed inboxes cost?

Accepted Answer

Prewarmed inbox packages start at $18/month for 3 inboxes with a free prewarmed .COM/.CO domain on quarterly billing ($24 month-to-month). Google Workspace fresh inboxes start at $2.00/inbox/month at volume.

Question 5

Which email providers do you support?

Accepted Answer

We provide email accounts on Google Workspace and Microsoft 365/Azure.

Question 6

Can I use my own domains?

Accepted Answer

Absolutely. If you already own a domain, we can help you set it up with mailboxes and ensure everything is configured correctly for optimal performance.

Question 7

What is your refund policy?

Accepted Answer

Sales are final once a licence has been activated or setup has begun. The one exception is an unused licence: a refund may be considered under the Refunds section of our Terms if the licence was never activated or accessed, no setup or resources were allocated, and you ask within seven days of purchase. Review the Refunds section of our Terms at https://warminboxes.com/terms or reach out with any questions before making a purchase.

Criterion	WarmInboxes	Sending.ac
Price	Prewarmed Google or Microsoft $6–$8 per inbox per month by billing cycle, free prewarmed .COM/.CO domain included. Azure tenants $50–$69 per month for up to 100 inboxes. Fresh inboxes on your own domains: Google $2.00–$3.50, Microsoft 365 $2.00–$3.00, Azure tenant $50. (source)	Pricing dynamic client-side; monthly figures cannot be reliably read from public HTML. (source: sending.ac)
Provider type	Official, licensed Google Workspace, Microsoft 365 and Microsoft Entra (Azure) tenants. Isolated per customer: no shared tenants, you hold admin on every mailbox. (source)	Isolated Azure tenants (Google waitlist on FAQ) (source: sending.ac)
Setup time	Delivered within 48 to 72 hours of payment, prewarmed and fresh alike, DNS included. Prewarmed sends the day it lands; fresh after 14 to 21 days of warmup. (source)	First domain set same day, warmup still weeks. (source: sending.ac)
Domain ownership	Prewarmed orders include a prewarmed .COM or .CO domain registered by us; fresh orders run on domains you own or buy through us. The Terms of Service set out the domain term and what cancelling does to it. (source)	Customer picks aged domains. (source: sending.ac)
DNS setup	SPF, DKIM, DMARC and forwarding configured before handover and verified by hand against a delivered message, on every platform. (source)	SPF/DKIM/DMARC verified before first send. (source: sending.ac)
Warmup	Prewarmed inboxes arrive already warmed. Fresh inboxes are warmed by our technicians for 14 to 21 days. Once the inboxes are connected to your sequencer, its own warmup is switched on and runs alongside your campaigns, and we switch ours off, so the mailboxes are never warmed by two systems at once. An AI agent sends but does not warm, so tell us the inboxes are going to an agent: we keep them in our warmup pool for free, or you can connect an external warmup tool. (source)	Prewarmed stock and warming / testing. (source: sending.ac)
API access	REST API at api.warminboxes.com/v1 with read, write and orders:place scopes, a one-file CLI, and a sandbox where test keys run the same routes without charging. Reference published verbatim on this site. (source)	API documented and sandbox advertised. (source: sending.ac)
MCP support	Two MCP servers: a keyless public one exposing every free deliverability check read-only, and an authenticated one on the account that previews and places orders, follows builds and exports into sequencers. (source)	MCP server advertised. (source: sending.ac)
Sequencer integration	Direct export into Instantly, Smartlead, PlusVibe and EmailBison from the portal or the API; any IMAP/SMTP or OAuth tool from the credentials you hold. (source)	Smartlead, Instantly, PlusVibe, EmailBison native. (source: sending.ac)
Support	24/7 WhatsApp with operators who run cold email campaigns themselves, plus email. No ticket queue. (source)	Deliverability advisor. (source: sending.ac)
Replacement policy	The 7-Day Placement Replacement Guarantee. Follow the sending requirements, and if an eligible newly delivered inbox fails our placement standard (warm primary inbox placement) during its first seven days, we replace that inbox at no charge. Send us the evidence (a placement test, bounces or headers) within those seven days and our team assesses it. Placement itself is not guaranteed: the receiving providers make every filtering decision. Replacements after the first week are not free. (source)	30-day replacement insurance eligibility varies; early access noted. (source: sending.ac)
Testing methodology	Published: a dated placement test log with senders and seed accounts, a SURBL blocklist study and a Google sender reputation study by top-level domain, each with sample sizes and what the method cannot see. (source)	Says hourly placement and 7 checks/day, fleet-based measurement; no complete sample. (source: sending.ac)
Real observations	Our own agency sends more than a million cold emails a month on this infrastructure, and the studies above are drawn from that sending. (source)	Claims internal sending on own infrastructure and deliberate domain burn tests. (source: sending.ac)

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