Rainbow Bridge vs Convly: Which Slack-Teams Bridge Delivers Full Message Fidelity?

Cross-platform messaging between Slack and Microsoft Teams is no longer a nice-to-have. It is an operational requirement for any organization running both tools. As the market for Slack-Teams sync tools matures, newer entrants like Rainbow Bridge and Convly have emerged alongside legacy players. Both promise to bridge the gap, but they approach the problem very differently.

If you are an IT manager evaluating a conv.ly alternative or comparing these two platforms head-to-head, this article breaks down exactly where they diverge on features, security, and scalability so you can make a confident decision.

For a broader view of the landscape, see our roundup of the best Slack Teams integration tools available in 2026.

Quick Overview: Two Newer Entrants, Different Philosophies

Convly positions itself as a lightweight Slack Teams bridge. It is newer to the market, built around a clean UX and a streamlined setup flow. For teams that need a basic messaging relay between a small number of channels, Convly can get you started quickly. The onboarding is minimal, and the interface is uncluttered.

Rainbow Bridge takes a different approach. While it is also a newer entrant, Rainbow Bridge was built from day one for full message fidelity and enterprise-grade requirements. That means thread sync, reaction mirroring, file sharing, edit and delete propagation, granular admin controls, and a clear path toward SOC 2 compliance. It is designed for organizations that cannot afford lossy communication between platforms.

Both tools solve the same core problem. The difference is how far each one carries you as your needs grow.

Feature Comparison Table: Rainbow Bridge vs Convly

The table below covers the capabilities that matter most when evaluating a Slack Teams sync tool for production use.

Feature	Rainbow Bridge	Convly
Basic message sync	Yes	Yes
Thread sync	Full thread preservation across platforms	Not supported
File sharing	Files forwarded with preview and download link	Limited or unsupported
Reaction sync	Emoji reactions mirrored in real time	Not supported
Edit propagation	Edits reflected on the other platform	Not supported
Delete propagation	Deletions reflected on the other platform	Not supported
Admin controls	Granular per-channel and per-user permissions	Basic admin dashboard
Compliance certifications	On SOC 2 certification path; data encryption at rest and in transit	Unclear; no public documentation on compliance
Scalability	50+ channel pairs supported	Designed for a handful of channel pairs
Setup time	Under 10 minutes per channel pair	Under 5 minutes for basic setup
Pricing	Free trial, then tiered plans starting at $19/mo	Free tier available; paid plans not well documented

The pattern is clear. Convly covers basic text relay. Rainbow Bridge covers the full spectrum of message types and metadata that teams rely on for day-to-day collaboration.

Message Fidelity: Where the Gap Widens

The single biggest differentiator in a Rainbow Bridge vs Convly comparison is message fidelity. In practice, "message fidelity" means that what someone types in Slack arrives in Teams looking, feeling, and behaving the same way it would natively.

Threads

Threaded conversations are how modern teams keep context organized. When a Slack thread has 15 replies, those replies need to appear as a coherent thread in Teams, not as a flat stream of disconnected messages. Rainbow Bridge preserves threaded structure. Convly does not currently sync threads, which means replies in Slack appear as standalone messages in Teams. For fast-moving channels, this creates confusion fast.

Reactions

Emoji reactions carry real meaning in Slack culture: approvals, acknowledgments, votes. Rainbow Bridge mirrors reactions across platforms in real time. With Convly, reactions stay siloed, which breaks lightweight approval workflows many teams depend on.

Edits and Deletes

People edit messages to fix typos, update information, and correct mistakes. They delete messages to retract them. Rainbow Bridge propagates both edits and deletes to the other platform, keeping the conversation accurate on both sides. Convly does not propagate edits or deletes, so the Teams side can show outdated or retracted content indefinitely. For compliance-sensitive organizations, this is a non-starter.

File Sharing

Sharing files across Slack and Teams is a common workflow, from screenshots to PDFs to design assets. Rainbow Bridge forwards shared files with a preview and a download link so recipients can access them natively. Convly has limited support here, and shared files may not carry over reliably.

If you want a deeper look at how bridging works end-to-end, our guide on how to connect Slack and Microsoft Teams walks through the process step by step.

Setup and Onboarding

Credit where it is due: Convly has a clean onboarding experience. The interface is simple, the flow is linear, and for a basic two-channel relay you can be up and running in under five minutes. For a small team testing the waters, that low friction is appealing.

Rainbow Bridge takes slightly longer per channel pair, typically under ten minutes, because it offers more configuration options up front. You choose which message types to sync, set permissions for who can manage the bridge, and configure notification preferences. That extra setup time pays dividends once you are running 10, 20, or 50+ channel pairs and need consistent governance across all of them.

Both tools use OAuth-based authentication for Slack and Teams, so there is no complex service account provisioning required for either.

Admin Controls and Governance

For IT managers responsible for communication governance, admin controls are not optional. They are essential.

Rainbow Bridge provides granular, per-channel permissions. You control which users can create, modify, or remove bridges. You can enforce naming conventions, restrict which Teams channels are eligible for bridging, and maintain a centralized audit view of all active connections. As your organization scales, these controls prevent sprawl and keep your communication architecture manageable.

Convly offers a basic admin dashboard. It covers the fundamentals, such as listing active bridges and toggling them on or off. But there is limited documentation on more advanced governance features like role-based access, audit logging, or policy enforcement. For a team of five running two bridges, that is fine. For an enterprise with dozens of cross-functional channel pairs, you need more.

Security and Compliance

This is perhaps the most critical area where the two tools diverge, and it is one where vague answers should be treated as red flags.

Rainbow Bridge encrypts data at rest and in transit. The platform is on a clear path toward SOC 2 Type II certification, with documented security practices and a transparent approach to data handling. For organizations in regulated industries or those with strict vendor security review processes, this matters.

Convly does not have publicly available documentation on its security posture or compliance certifications. There is no mention of SOC 2, ISO 27001, or equivalent frameworks on its website or in its help center. For personal projects or small teams with low regulatory exposure, this may be acceptable. For enterprise procurement, it is a blocker.

If your organization requires a vendor security assessment before deploying new SaaS tooling, make sure to request Convly's security documentation directly. The absence of public information does not necessarily mean the product is insecure, but it does mean you will need to do more diligence on your own.

Scalability: A Handful vs Fifty-Plus

Convly is designed for simplicity, and that simplicity has trade-offs when it comes to scale. The product works well for a small number of channel pairs, typically fewer than ten. Beyond that, the lack of advanced admin controls, limited documentation, and absence of enterprise-grade features make it difficult to manage at scale.

Rainbow Bridge was built to handle 50+ concurrent channel pairs without degradation. The admin dashboard provides a centralized view of all bridges, health status, and message throughput. If your organization is growing or if you anticipate cross-platform communication expanding across departments, Rainbow Bridge is the tool that scales with you rather than becoming a bottleneck.

Scalability is not just about message volume. It is about operational overhead. Managing 50 bridges without proper admin tooling, audit trails, and permission structures creates a maintenance burden that falls squarely on your IT team.

Pricing

Convly offers a free tier, which is attractive for initial testing. Paid plans are not well documented publicly, so you may need to contact their team for enterprise pricing. The free tier is likely limited in the number of channel pairs or message volume.

Rainbow Bridge offers a free trial so you can validate the experience before committing. Paid plans start at $19 per month for the Light tier, which covers smaller teams, with a Pro tier at $49 per month for organizations that need more channel pairs and advanced features. Enterprise pricing is available on request for large-scale deployments. The pricing is transparent and published, which simplifies procurement.

When Convly Might Be the Right Choice

Convly is a reasonable option if you need a basic, lightweight messaging relay between one or two Slack and Teams channels, you do not require thread sync, reaction mirroring, or edit and delete propagation, your organization has no strict compliance or security audit requirements, and you are a small team testing cross-platform communication for the first time.

For that narrow use case, Convly's simplicity is a genuine advantage.

When Rainbow Bridge Is the Better Fit

Rainbow Bridge is the stronger choice when you need full message fidelity including threads, reactions, files, edits, and deletes. It is the better fit when your organization requires or is moving toward SOC 2 compliance, when you are managing more than a handful of channel pairs, when granular admin controls and audit trails are requirements, and when you need a tool that will scale as cross-platform communication grows across your company.

For a comparison with another tool in this space, see our Rainbow Bridge vs Conclude Connect breakdown.

The Bottom Line

Convly is a clean, early-stage product that handles basic messaging relay well. If your needs are simple and your scale is small, it can work. But for IT managers who need a Slack Teams sync tool that delivers full message fidelity, enterprise-grade security, and the ability to scale to dozens of channel pairs, Rainbow Bridge is purpose-built for that job.

The question is not whether both tools can send a message from Slack to Teams. They both can. The question is whether the message arrives with full context, whether your compliance team can approve the vendor, and whether the tool still works when you have 50 bridges running instead of two. On all three counts, Rainbow Bridge delivers.