What are the best open source alternatives to HEY?

The top open source alternatives to HEY include UnInbox. These tools offer similar functionality while being free and open source.

Why choose an open source alternative to HEY?

Open source alternatives provide transparency, community support, no vendor lock-in, and often cost savings. You can customize the software to your needs and have full control over your data.

Are these HEY alternatives really free?

Yes, all listed alternatives are open source and free to use. You may need to pay for hosting if you self-host, but the software itself is free.

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Open Source HEY Alternatives

A curated collection of the 1 best open source alternatives to HEY.

The best open source alternative to HEY is UnInbox. If that doesn't suit you, we've compiled a ranked list of other open source HEY alternatives to help you find a suitable replacement.

HEY alternatives are mainly Team Chat & Messaging Tools but may also be Email Clients. Browse these if you want a narrower list of alternatives or looking for a specific functionality of HEY.

Written by Piotr Kulpinski

Last updated: October 20, 2026

HEY

Email service with a screener that blocks unwanted senders, a separate feed for newsletters and a paper trail for receipts, keeping your inbox focused.

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UnInbox revolutionizes team email management with a powerful open-source platform designed for modern business collaboration. Teams can work together seamlessly through shared inboxes, with the ability to comment on conversations and reply from shared addresses, eliminating confusing email chains.

Key features include:

Shared spaces for team collaboration and communication
Workflow status tracking for clear task management
Unlimited custom email addresses (support@, sales@, etc.)
Flexible workflow management with up to 3 workflows per space
Team assignment capabilities for better task distribution

The platform offers tiered pricing options from Free to Enterprise, making it accessible for businesses of all sizes. The Pro plan includes advanced features like unlimited custom domains, SMTP & API access, and priority support, while Enterprise customers get additional security features like SAML SSO and dedicated instances.

Perfect for teams who need to manage multiple email addresses, track response statuses, and collaborate effectively on email communications. The open-source nature ensures transparency and customization possibilities for organizations.