How Does turboSMTP's Email Deliverability Compare to Other SMTP Providers?

turboSMTP advertises a 99% deliverability rate, compared with roughly 70% for free SMTP services and 82% for other SMTP providers, according to figures published on serversmtp.com. If inbox placement is your main selection criterion, that gap is the headline number. But the comparison is only meaningful if you know what "deliverability" covers here, how the provider claims to achieve it, and how to verify your own results after switching.

What the published deliverability numbers say

The site presents three figures side by side:

These are vendor-published marketing figures, not an independent benchmark. Treat them as a directional claim rather than a measured result for your specific sending domain. The useful takeaway is the positioning: turboSMTP sells itself as a deliverability-focused relay, not as the cheapest option.

Why the claimed gap exists

The page attributes the difference to a "trusted and authenticated SMTP relay service." In practice, that means the provider handles the parts of email infrastructure that most affect inbox placement:

• Authenticated relay — your mail leaves through servers with established sending reputation rather than an unauthenticated or shared-IP setup.
• Worldwide server and IP infrastructure — servers and IP addresses in Europe, the USA, the Middle East, and Asia, which lets you send from a region appropriate to your recipients and to different regulatory environments.
• GDPR compliance — the provider states it is 100% GDPR compliant, which matters if you send to EU recipients and need a processor that meets those obligations.

A free SMTP service typically gives you a shared, low-reputation path with little control over authentication or IP standing. That is the most common reason free-tier sending lands in spam or gets throttled.

What deliverability affects in practice

The distinction matters differently depending on what you send:

• Transactional email (order confirmations, password resets) — a missed delivery is a broken user flow, not just a missed impression. The page specifically calls out immediate arrival for these messages.
• Newsletter and marketing campaigns — deliverability directly caps your open rate, since an email that never reaches the inbox cannot be opened.

The case study referenced on the site (Valerio Fioretti, on doubling delivery and open rates with turboSMTP) is the provider's own example of this effect. It is a customer story published by the vendor, so read it as an illustration of the mechanism rather than independent proof.

How to verify deliverability for your own sending

Do not rely on the headline percentage. Check your actual results:

1. Send a test batch through turboSMTP to a mix of real inboxes (Gmail, Outlook, a corporate domain).
2. Open the delivery tracking reports — the page states turboSMTP provides detailed real-time reports tracking outgoing and opened emails.
3. Compare against your current provider using the same recipient list and the same message content.
4. Check placement, not just delivery — a message can be "delivered" to the spam folder. Confirm inbox placement manually for the test batch.
5. Watch the first weeks after switching — reputation builds over time, so early results on a new sending domain may differ from steady state.

The tracking reports are the part you can act on: they tell you whether the 99% claim holds for your traffic.

Choosing between turboSMTP and alternatives

Use the same criteria across providers:

turboSMTP is the stronger fit if inbox placement and compliance matter more to you than the lowest possible cost, and if you want human support rather than a ticket queue. A free or budget SMTP service may be adequate if you send low volumes of non-critical mail and can tolerate lower placement.

The honest limit of this comparison: the 70%/82%/99% figures come from the vendor, and no independent deliverability test is included in the source material. Run your own test batch before committing, and use the tracking reports to confirm the result.