sending.ac

Sending.ac is a cold email infrastructure platform that takes a radically different approach to high-volume outreach. Instead of forcing senders to rotate dozens of domains with a few mailboxes each, it lets you send thousands of emails per day from just a handful of domains -- sometimes even a single domain. The platform is built on Azure and automates the entire technical setup, from DNS authentication to mailbox provisioning, in seconds. It also includes an accelerated warm-up engine that gets domains ready in days rather than weeks.

What makes sending.ac stand out is its isolation architecture. Each domain gets its own Azure tenant, unique IP addresses, tenant-specific DKIM keys, and separate IMAP per user. This level of isolation is rare among cold email infrastructure providers and directly addresses the deliverability risks that come with shared environments. The result is a setup that can outperform 25+ Gmail or Outlook domains from a single domain, according to the company.

The platform is designed for serious senders -- lead gen agencies, outbound teams, and GTM operations that send 30,000+ cold emails per month or manage over 100 mailboxes. It eliminates the headache of buying and managing hundreds of domains, which can cost $1,500+ per month. With sending.ac, you can run up to 150 inboxes on one domain, saving over $1,000 in domain costs alone. The pricing is per inbox, currently $0.44 per month (rising to $0.50 on June 30), which is competitive for the level of infrastructure provided.

Setup is fully automated. You connect a domain, and the platform handles SPF, DKIM, DMARC, and mailbox creation in about 34 seconds per inbox. There is no need for a VA or manual DNS configuration. The warm-up process is also built in, so you can start sending at scale much faster than with traditional setups. The platform's focus on automation and isolation means you spend less time on infrastructure and more on campaign strategy.

Sending.ac is best for teams that have outgrown basic email setups and need a reliable, scalable infrastructure without the operational overhead of managing dozens of domains. it's less suited for small-scale senders or those who prefer transparent, self-serve pricing tiers. The lack of public case studies and user reviews makes it harder to evaluate, but the technical approach is sound and addresses a real pain point for high-volume cold emailers.

Overall, sending.ac is a strong contender in the cold email infrastructure space, especially for agencies and outbound teams that prioritize deliverability and operational efficiency. Its domain isolation and automated setup are genuine differentiators. If you're tired of juggling domains and want a single, robust infrastructure that scales, sending.ac is worth a serious look.