vs
NimblyMail vs FluentSMTP
FluentSMTP has no paid tier and gives away routing and failover. NimblyMail adds a background queue, recurring deliverability audits and multisite. Neither is better in the abstract.
Claims on this page were checked against FluentSMTP 2.3.x, August 2026.
Which one should you use?
Choose FluentSMTP if…
- You want smart routing or a fallback connection without paying — FluentSMTP includes both free, and NimblyMail puts them in Pro.
- Your site is a single install with steady, modest mail volume.
- You would rather have no licence to renew, ever.
Choose NimblyMail if…
- You run a WooCommerce store and do not want mail sending inside the checkout request.
- You want deliverability checked on a schedule instead of by hand.
- You run multisite, or build staging copies of client sites regularly.
The differences that matter
Mail sends inside the checkout request
FluentSMTP has no background send queue, so a WooCommerce order confirmation is transmitted while the customer waits for the confirmation page. Version 2.3.0 added SMTP connection reuse within a bulk sending session, which is connection pooling inside one request rather than deferral — wp_mail() still blocks. Two consequences: checkout is slower, and a transport error at the wrong moment can fail the request after the order is created and paid, which produces duplicate orders when the customer retries.
Deliverability is checked once, or continuously
FluentSMTP can alert you when a connection fails. It does not check whether receiving servers can verify your mail. NimblyMail audits six pillars — SPF, DKIM, DMARC, PTR, connectivity and queue health — weekly, reads the expected SPF include and DKIM selector from your configured mailer so it names the exact missing record, and opens a real TCP connection rather than performing a DNS lookup.
A kill switch, or a sandbox
Both can stop a staging site mailing customers, and the difference is narrower than most comparison pages pretend. FluentSMTP has Email Simulation: a global on/off that logs without sending, with an admin-bar indicator. NimblyMail adds a redirect mode that sends everything to one safe address while preserving the original recipients in headers, and an allowlist evaluated against every To, Cc and Bcc — so one customer address sandboxes the whole message rather than letting it out.
Multisite
FluentSMTP has no network administration; configuration is per-subsite. NimblyMail includes it free: network defaults, per-site overrides, and lockable fields, resolved in a defined order of PHP constant, network lock, site override, network default, plugin default. Irrelevant on one site, decisive on forty.
Capability comparison
| Capability | FluentSMTP | NimblyMail |
|---|---|---|
| Email logging | Free | Free |
| Resend from log | Free | Free |
| Smart routing by sender | Free | Pro |
| Fallback / backup connection | Free | Pro |
| Background sending queue | Not available | Included |
| Per-message queue priority | Not available | Included |
| Recurring deliverability audit | Not available | Included |
| Stop all sending on staging | Included | Included |
| Sandbox redirect mode + allowlist | Not available | Included |
| Multisite network admin with field locks | Not available | Included |
| Email rate limiting | Not available | Pro |
| Scheduled reports | Not available | Pro |
| Paid tier exists | Not available | Included |
FluentSMTP pricing: Free, with no paid tier at all.
Moving from FluentSMTP
NimblyMail detects FluentSMTP and migrates its settings — and this is the migration path that recovers the most. FluentSMTP encrypts its stored credentials, and rather than skipping them the importer calls FluentSMTP's own decryption routine, so your SMTP password, SES secret key and API keys transfer intact. Migrating from WP Mail SMTP, by contrast, cannot recover the SMTP password at all. Log settings, retention period and failure-alert configuration come across too, and if you keep credentials in wp-config.php using FluentSMTP's key-store mode, the importer names the exact NimblyMail constant to define instead. OAuth connections must be re-authorised: tokens are issued against one application's redirect URI and cannot be transferred between plugins. Both plugins can stay active during the switch.
Questions worth asking before switching either way
Does your checkout speed actually matter? If you take a handful of orders a day, a two-second checkout delay is a real cost that nobody will ever notice. If you take hundreds, it is measurable revenue. Be honest about which you are.
How many sites do you manage? One site makes multisite administration irrelevant, and free routing more valuable than anything on our side of the table. Forty inverts that completely.
Who fixes it when mail breaks? If that is you, and you would find out from a customer, a scheduled audit is worth more than a feature list suggests.
Do you clone sites? Agencies do this constantly, and the sandbox distinction is the difference between “staging cannot send” and “staging can send to us and nobody else”. If you never build staging copies, ignore it entirely.
A plugin that wins on features you do not use is not the better plugin for you. FluentSMTP is genuinely the right answer for a large number of sites, and we would rather you chose correctly than chose us.
NimblyMail vs FluentSMTP, answered
Yes. FluentSMTP has no paid tier, and its email logging, smart routing, fallback connection and provider integrations are all in the free plugin. Routing and fallback in particular are free there and are Pro features in NimblyMail, so if those are what you need, FluentSMTP gives them to you at no cost.
No. FluentSMTP sends mail inside the request that generated it, so a WooCommerce checkout waits for the SMTP handshake and transmission before the confirmation page renders. Version 2.3.0 added connection reuse within bulk sending sessions, which is connection pooling rather than deferral.
Yes. FluentSMTP has Email Simulation, a global on/off that logs mail without sending it and shows an indicator in the admin bar. It has no redirect mode and no recipient allowlist, so you cannot let specific addresses through or view rendered mail in a real inbox while staging is protected.
Most of them, including encrypted credentials. NimblyMail calls FluentSMTP's own decryption routine, so SMTP passwords, SES secret keys and API keys transfer intact, along with log settings, retention period and failure-alert configuration. OAuth connections to Gmail or Microsoft 365 must be re-authorised, because tokens are bound to a specific application.
Other comparisons
View all comparisons
WP Mail SMTP
compared with NimblyMail
The market leader, with a free tier that connects a mailer and little else. Logging, alerts, routing, reports and multisite are all…
15 capabilities compared
Read the comparison
Easy WP SMTP
compared with NimblyMail
Easy WP SMTP is simple to set up, and its free version is thinner than its marketing suggests: Gmail, Microsoft 365, Amazon…
14 capabilities compared
Read the comparison