Connect Slack to external communications

For small teams and individuals that manage a small amount of external messages and want to enjoy all of MailClark
unlimited inboxes in Slack
100 messages/m
Pay per inbox
For teams wanting to connect a few Slack channels to email and social media, with no limit on messages.
Up to 4 inboxes in Slack
unlimited messages
For startups and business relying on Slack for internal communications and eager to integrate external communications.
unlimited inboxes in Slack
unlimited messages
from $69/m
For companies that run on multiple Slack workspaces and/or have special needs.
unlimited inboxes in Slack
unlimited messages
Unlimited users
Unlimited contacts
Multiple workspaces
Connect Slack to:
Google Groups
Custom domain
Custom SMTP
Priority support
24/7 support
Account manager
Tailored settings
Pay per inbox

Pay in $ USD or € EUR. We offer discount to nonprofits (read below).

Can I use MailClark for free?

Yes! No credit card required. The free version is limited to 100 emails/messages per month.

Do you offer discount to nonprofit organizations?

Yes. If your organization has been approved for the Slack for Nonprofits program, we’d be happy to offer your team the Unlimited Plan (worth $39/m) free of charge.

To be upgraded to the Unlimited Plan as a non-profit, forward the email you received from Slack which confirms your approval to the non-profit program at

Note: We do not offer refunds for subscription fees paid prior to being approved.

What happens when I reach the limit of the free inbox?

Each month, after 100 emails & tweets have been sent/received, only the headers (e.g. author) are posted in Slack. Subscribing to a paid account allows you to view the messages’ contents and resumes normal posting.

I’ve just created a new inbox, how will that be billed?

If you’re on the Unlimited Plan, no worries, you pay a fixed $39/m for as many inboxes as your team needs.

If you pay per inbox, we wait till a few emails or tweets have been sent/received in the new inbox—in case MailClark was invited by mistake—before adding $9 to your subscription.

How do I view my invoices or manage my subscription?

Type settings in a Slack’s Direct Message to MailClark, and then click the ‘Billing portal’ link under ‘Billing’.