Aerosend vs Infraforge: Shared SMTP vs Dedicated IP for Cold Email (2026)

Aerosend uses shared SMTP pools with recycled IPs. Infraforge sells dedicated IPs. Neither is what most cold email operations should be running — but they are not comparable products. Full breakdown.

Aerosend vs Infraforge: Not the Same Product

Aerosend and Infraforge are often lumped together as "cold email SMTP providers." They are not equivalents. Infraforge sells dedicated IP infrastructure with a known reputation isolation model. Aerosend sells access to shared SMTP pools with recycled IPs that carry prior-sender reputation damage. The comparison matters because buyers evaluating these two options as interchangeable are making a decision that materially affects deliverability.

Feature	Puzzle Inbox	Infraforge
Infrastructure type	Shared SMTP pool	Dedicated IP per customer
IP reputation isolation	—	✓
IP history auditable	—	At provisioning
Published track record	None	Case studies
Cold email deliverability	Poor (Reddit-documented)	Depends on warm-up
Pricing tier	Custom	Premium enterprise

The Structural Difference

Aerosend: Shared SMTP infrastructure. New customers are provisioned onto IP pools that have been used by prior senders. There is no clean-IP inventory and no published pool rotation. Reddit r/Coldemail threads through 2025 and 2026 document a consistent pattern of new Aerosend accounts hitting Gmail spam on the first send — the signature of low-reputation IPs being reassigned.

Infraforge: Dedicated IP per customer with a warm-up runway. The customer owns the IP reputation from day one. Reputation starts at zero and builds with sending discipline, which takes four to six weeks. During warm-up, deliverability is unpredictable. After warm-up, the customer controls the reputation.

No Verifiable Track Record for Aerosend

Aerosend does not publish inbox placement testing data, named agency case studies, or third-party verifiable results. Infraforge publishes case studies with named enterprise customers. Neither has the transparency of a G2 or Trustpilot presence with hundreds of reviewers, but Infraforge has documented operational history that Aerosend does not.

Cold Email Deliverability

Aerosend cold email placement rates on Gmail reported by operators sit in the 40 to 60 percent inbox range. Infraforge post-warmup placement typically reaches 70 to 85 percent depending on sending discipline. Authenticated Google Workspace from providers like Puzzle Inbox reaches 85 to 90 percent on the same target lists without warm-up delay. The gap between Aerosend and either alternative is not small.

Neither Is the Right Default for Cold Email

For cold email volumes under 50K per day (which covers 90 percent of operations), neither shared SMTP nor dedicated SMTP is the right infrastructure choice. Authenticated Google Workspace and Microsoft 365 mailboxes inherit Google and Microsoft IP reputation and get better placement out of the box than either SMTP option. The SMTP category exists for extreme volume operations at 100K+ per day with dedicated deliverability engineering — a small fraction of the cold email market.

Verdict: Between the two, Infraforge is the safer choice because reputation is isolated to the customer. Aerosend's shared-pool model with recycled IPs and no track record is not recommended for cold email. For most cold email operations, real Google Workspace or Microsoft 365 beats both at lower cost and higher placement.

Aerosend vs Infraforge: what cold email operators actually need to compare

Most "Aerosend vs Infraforge" comparisons online compare feature checkboxes. Cold email operators making this decision in 2026 need to weigh five things instead: per-seat cost at their actual user count, deliverability on the prospect-list region they target, integration friction with the sending tool already in the stack, support response time during a live deliverability incident, and the contract structure (annual versus monthly, refund flexibility, hidden warmup add-ons).

Pricing comparison: Aerosend vs Infraforge

Headline pricing is the first thing most buyers see, but real total cost of ownership depends on what is bundled and what is an add-on. For Aerosend and Infraforge, the dimensions to model carefully are: per-seat cost on the smallest viable plan, the price step from the entry tier to the next tier (where most growth-stage teams end up), credits or sending limits that bottleneck heavy users, warmup tool subscriptions sold separately, deliverability monitoring add-ons, and any minimum-order constraints that inflate the entry point. Pull current pricing directly from the vendor pricing pages; both vendors update tiers quarterly in 2026.

Deliverability and sending infrastructure

For tools in the cold email infrastructure category, the upstream question is which underlying mailbox provider the sending traffic actually leaves from. Real Google Workspace and Microsoft 365 mailboxes inherit Google's and Microsoft's own IP reputation. Custom SMTP infrastructure does not. India-region Workspace tenants carry different region-level reputation signals from US or EU region tenants. If Aerosend and Infraforge differ on this dimension, that single difference outweighs most of the feature comparison. For sending tools and lead data tools, the upstream question is whether the product gracefully connects via OAuth to real GWS / M365 mailboxes from a provider like Puzzle Inbox.

Integration friction with the existing stack

Most operators do not pick Aerosend or Infraforge in isolation. The decision is shaped by what the rest of the stack already runs on. If the team is on Smartlead or Instantly for sending, the integration story is more important than any standalone feature comparison. If the team is on Apollo or Clay for data, the export and webhook compatibility matters more than the prospect database size. The right comparison framework is: "Which one breaks least when bolted onto our existing stack?" not "Which one has more features on a vendor demo deck?"

Support and incident response

Both Aerosend and Infraforge have public support channels. The dimension that separates them is response time during a live incident — a deliverability drop mid-campaign, a sudden bounce-rate spike, an account suspension. Test this before signing by opening a real support ticket on a free trial or paid plan. The vendor that responds in hours instead of days is the one that survives contact with a real cold email operation.

Where Puzzle Inbox fits

Whichever of Aerosend or Infraforge the team picks, the sending infrastructure layer is upstream of the tool decision. Puzzle Inbox provisions real Google Workspace and Microsoft 365 cold email mailboxes on dedicated tenants, ships pre-warmed inventory in 24 to 72 hours, and connects via OAuth (email + password) to every sending tool in this comparison. See the pricing page, Google Workspace plans, or Outlook 365 plans for current per-inbox numbers. Reviews follow our published editorial methodology.

Aerosend vs Infraforge FAQ

Which is cheaper, Aerosend or Infraforge?

The cheaper of Aerosend and Infraforge at your specific seat count depends on the tier each vendor places you on. Pull current pricing from both vendor pricing pages on the same day and run the math at your actual user count, your actual sending volume, and your actual feature requirements. The cheaper headline number is often not the cheaper effective cost once add-ons and seat tiers are factored in.

Which has better deliverability, Aerosend or Infraforge?

Deliverability is mostly a function of the sending mailbox provider (Google Workspace, Microsoft 365, or custom SMTP) rather than the tool layered on top. If Aerosend and Infraforge both connect to real GWS or M365 mailboxes, the deliverability difference is small. If one of them is custom SMTP infrastructure and the other is real GWS / M365, the gap is large.

Can I switch between Aerosend and Infraforge later?

Both vendors export contact data, campaign history, and reply data in standard formats. Migration friction is mostly in re-onboarding the team on the new UI rather than data portability. Budget a week for the switch.

What is a good alternative to Aerosend and Infraforge?

The alternatives most cold email operators evaluate alongside Aerosend and Infraforge live in the same category. See the tools directory for the full category list and the comparisons directory for related head-to-heads.

Ready to start sending?

Puzzle Inbox provisions pre-warmed Google Workspace and Outlook 365 cold email inboxes ready to send within 24-72 hours. See the pricing page, the how-it-works walkthrough, or the our-process page for full details. Comparisons follow our editorial methodology.