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Warmerly TrulyInbox
One-to-one · Supported mailboxes

Supported mailboxes

One row, in depth: what each tool does, the verified numbers, and who each suits.

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TrulyInbox details read from its pricing page, home, features, how-it-works, network, why-trulyinbox and agencies pages, V2 blog post, refund policy, terms, privacy policy, API docs and help centre on 21 October 2026.

Warmerly

Gmail and Google Workspace, Outlook and Microsoft 365, Zoho, Namecheap Private Email, and custom SMTP and IMAP.

TrulyInbox

Google and Microsoft by OAuth, Yahoo and AOL by app password, others by SMTP and IMAP, sending services such as SendGrid and Amazon SES, and CSV bulk import.

The short answer

Supported mailboxes, in one look.

Warmerly connects Gmail and Google Workspace by app password, Microsoft by sign-in, and Zoho, Namecheap and anything with SMTP and IMAP settings. TrulyInbox is ahead on reach: its pages name 18+ providers, use OAuth for Google and Microsoft, and also warm sending services such as SendGrid and Amazon SES. Last checked 21 October 2026.

Warmerly

Gmail and Google Workspace, Outlook and Microsoft 365, Zoho, Namecheap Private Email, and custom SMTP and IMAP.

TrulyInboxTrulyInbox ahead on this row

Google and Microsoft by OAuth, Yahoo and AOL by app password, others by SMTP and IMAP, sending services such as SendGrid and Amazon SES, and CSV bulk import.

The picture

Drawn side by side.

What you can connect

As each lists it

WarmerlyTrulyInbox

Five presets and custom SMTP

  • Gmail and Google Workspace, app password
  • Outlook and Microsoft 365, sign-in
  • Zoho Mail
  • Namecheap Private Email
  • Custom SMTP and IMAP

18+ providers and sending services

  • Google and Microsoft, OAuth
  • Yahoo and AOL, app password
  • SendGrid, Mailgun, Amazon SES
  • CSV and API bulk import

TrulyInbox names more. Warmerly connects over SMTP and IMAP settings and tests both before saving.

How Warmerly does it

Warmerly, in detail.

Five presets in the add-mailbox wizard, and manual SMTP and IMAP for the rest, with both directions tested before a mailbox is saved.

01

Five presets

The wizard has presets for Gmail and Google Workspace, Outlook and Microsoft 365, Zoho Mail, Namecheap Private Email, and custom SMTP and IMAP.

Warmerly product, checked 21 October 2026

02

How Google and Microsoft connect

Gmail and Google Workspace connect with a Google app password. Microsoft 365, Outlook.com and Hotmail connect through a one-click Microsoft sign-in.

Warmerly product, checked 21 October 2026

03

Everything else is manual

Zoho, Namecheap Private Email, IONOS, Hostinger and other hosts connect with SMTP and IMAP settings. We name no provider we have not tested, and we do not claim Yahoo or AOL.

Warmerly product, checked 21 October 2026

04

Both directions are tested

Warmerly signs in to SMTP to send and IMAP to read before it saves a mailbox, so a mailbox that cannot receive is rejected at connection, not discovered a week later.

Warmerly product, checked 21 October 2026

05

Caps follow the provider

Daily warmup quota is held to 40 on Gmail, 30 on Outlook and 25 on Zoho, and 50 on other providers.

Warmerly product, checked 21 October 2026

06

Hosted mailboxes

Mailboxes Warmerly hosts for you through OneMail do not use one of the plan's mailbox slots, which suits teams that do not yet have mailboxes.

Warmerly product, checked 21 October 2026

07

A bulk connect endpoint

The API has an endpoint that connects several mailboxes in one call. It is all or nothing on plan capacity: an import that would exceed the plan is refused whole. The API itself needs the Agency plan.

Warmerly product, checked 21 October 2026

How TrulyInbox does it

TrulyInbox, in detail.

A long provider list, OAuth for the two big providers, app passwords and SMTP for the rest, and relays as well as mailboxes.

01

18+ providers named

The home page names Gmail, Google Workspace, Outlook, Outlook.com, Microsoft 365, Yahoo, iCloud, AOL, Zoho, SendGrid, Mailgun, Amazon SES, Mailchimp, Brevo, Mailjet, Elastic Email, SendPulse, GetResponse and SMTP. Its FAQ adds GoDaddy, Yandex and GMX.

trulyinbox.com · read 21 October 2026

02

One-click OAuth for Google and Microsoft

How it works says one-click OAuth for Google and Microsoft, with SMTP and IMAP credentials for any other provider, and that no password is shared with OAuth.

trulyinbox.com/how-it-works · read 21 October 2026

What TrulyInbox does not say

We looked, and found no statement on these. That is about its published pages only, not about the product.

  • Which providers have tighter warmup volume caps, as no per-provider figure is published
  • Whether the 18+ providers all use the same warmup network or separate pools
  • Whether Cloudflare email addresses can be warmed: a help article asks the question and we did not read its answer
  • How OAuth tokens are stored beyond the statement that passwords are not

Where the sources disagree

We report each version rather than pick one.

  • The home page says 18+ providers and lists 19 names including SMTP, and its FAQ adds three more. We report the pages' own count and do not total them.
  • How it works says 'if you can send from it, we can warm it up' while its guide lists specific providers and asks whether Cloudflare addresses can be warmed. The claim is wider than the guide.
The numbers

Only what we could verify.

Supported mailboxes: Warmerly and TrulyInbox side by side. Warmerly is in the first column.
MeasureWarmerlyTrulyInbox
Supported mailboxesGmail and Google Workspace, Outlook and Microsoft 365, Zoho, Namecheap Private Email, and custom SMTP and IMAP.Google and Microsoft by OAuth, Yahoo and AOL by app password, others by SMTP and IMAP, sending services such as SendGrid and Amazon SES, and CSV bulk import.
Providers named5 presets18+
Google Workspace connectApp passwordOAuth
Microsoft connectSign-inOAuth
Sending services warmedNone named7 in its guide
Bulk importA bulk endpoint in the APICSV, API and 2 bulk guides
Gmail daily ceiling40 a dayNot stated
In practice

What it means for you.

Our reading of the facts above. Not a promise, and not the only reasonable reading.

1

Count the mailboxes you actually have

If everything you run is Google Workspace or Microsoft 365, both tools connect it, and the difference is OAuth against an app password. If you have Yahoo, AOL or a sending service, TrulyInbox names them and Warmerly does not.

2

An app password has a cost

Google app passwords need two-step verification on the account and are a credential you create and revoke yourself. OAuth is a sign-in and a revocable grant. Some teams prefer one, some the other.

3

Warming a relay is a different job

TrulyInbox says it warms sending services such as SendGrid and Amazon SES. Warmerly warms mailboxes it can sign in to over SMTP and IMAP, so a relay with no IMAP is outside what we claim.

4

Bulk connect matters at volume

If you add dozens of mailboxes at a time, TrulyInbox's CSV, bulk and API routes save clicks. Warmerly has a bulk connect endpoint in its API, which needs the Agency plan, and we describe no CSV import.

5

Provider caps are worth asking about

Warmerly publishes 40 on Gmail, 30 on Outlook and 25 on Zoho. TrulyInbox publishes a 100 a day ceiling per account and no provider split, so ask it what a Microsoft mailbox can do.

Who it suits

Pick the one that fits.

Warmerly

Warmerly is the better fit if

  • Your mailboxes are Gmail, Google Workspace, Outlook, Microsoft 365, Zoho or Namecheap
  • You want a connection test that checks both sending and reading
  • You want published per-provider warmup caps
  • You want hosted mailboxes without using a slot
TrulyInbox

TrulyInbox is the better fit if

  • You warm Yahoo, AOL, iCloud or GoDaddy mailboxes
  • You warm sending services such as SendGrid, Amazon SES or Mailgun
  • You want OAuth for Google Workspace and Microsoft
  • You connect many mailboxes at once by CSV, bulk or API
Questions
Which providers does TrulyInbox support?

Its pages name 18+, including Gmail, Google Workspace, Outlook, Microsoft 365, Yahoo, iCloud, AOL, Zoho, SendGrid, Mailgun, Amazon SES, Mailchimp and Brevo, plus any inbox that supports SMTP or OAuth.

Which providers does Warmerly support?

Presets for Gmail and Google Workspace, Outlook and Microsoft 365, Zoho Mail and Namecheap Private Email, plus custom SMTP and IMAP. Any other host works only if it gives you SMTP and IMAP settings.

Does either use OAuth?

TrulyInbox does for Google and Microsoft. Warmerly uses a Microsoft sign-in for Microsoft and a Google app password for Gmail and Google Workspace.

Can I warm a sending service rather than a mailbox?

TrulyInbox says yes for services such as SendGrid and Amazon SES. Warmerly warms mailboxes only.

Can I connect many mailboxes at once?

TrulyInbox offers CSV, bulk guides for Google Workspace and Microsoft 365, and a bulk API. Warmerly has a bulk connect endpoint in its API, on the Agency plan.

Sources

TrulyInbox pages were read on 21 October 2026. Plans and wording change, so check the vendor's own page before you decide. Warmerly details come from the product as it runs today.

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