--- title: "Classic CRM Cards Are Being Sunset: What to Do Before October 31, 2026" url: https://www.sidekickstrategies.com/hubspot-updates/hubspot-classic-crm-cards-sunset-app-cards-migration description: "HubSpot is sunsetting Classic CRM Cards on October 31, 2026. Learn what's changing, how to migrate to App Cards, and which portals and developers need to act no" type: article updated: 2026-11-09T22:25:01Z canonical: https://www.sidekickstrategies.com/hubspot-updates/hubspot-classic-crm-cards-sunset-app-cards-migration --- # Classic CRM Cards Are Being Sunset: What to Do Before October 31, 2026 > **Tip** > > TL;DR: HubSpot is retiring Classic CRM Cards. New Marketplace apps can't include them starting June 16, 2025, and all existing Classic CRM Cards must be migrated to React-powered App Cards by October 31, 2026. This matters most to developers, RevOps teams, and any portal using third-party integrations that display data in the CRM sidebar. ## What This Update Actually Is HubSpot is officially sunsetting Classic CRM Cards, the static sidebar components that developers have used for over a decade to display third-party data inside CRM records. The replacement is App Cards, which are built with React and powered by HubSpot's UI Extensions framework. App Cards support dynamic interactions, work across a wider range of CRM objects, and aren't locked to a single sidebar position. Here's the key timeline you need to know: - June 16, 2025: New Marketplace apps can no longer include Classic CRM Cards for listing or certification. - June 16, 2025: You can no longer add Classic CRM Cards to any HubSpot UI. - October 31, 2026: Existing Marketplace apps using Classic CRM Cards must be fully migrated to App Cards. Classic CRM Cards stop working entirely. Migration support resources are expected from HubSpot in November 2025. But waiting until then isn't a smart plan. ## Why HubSpot Shipped This Classic CRM Cards were built for an older version of HubSpot. They're static, meaning they can't respond to clicks or user input inside the card itself. They're also limited to the right sidebar and only work with a handful of standard CRM objects. The frustration for developers has been real. If you wanted richer interactions or needed to show data tied to a custom object, Classic CRM Cards simply couldn't do it. You were stuck with workarounds. App Cards solve that. They're React-based, interactive, and far more flexible about where and how they surface data. HubSpot has seen strong developer adoption since the UI Extensions framework launched. The Classic format doesn't have a future, so HubSpot is drawing a clean line. ## How to Use It Step by Step If you're a developer or RevOps leader managing integrations, here's the practical path forward. 1. Audit your current Classic CRM Cards. Log into your portal and identify every integration or custom app that surfaces a card in the CRM sidebar. Document which objects each card is attached to. 2. Check your Marketplace apps. If you use any third-party apps from the HubSpot App Marketplace, contact those vendors now. Ask them directly about their migration timeline to App Cards before October 31, 2026. 3. Review HubSpot's UI Extensions documentation. HubSpot has published beta resources including a UI customization overview, a UI Extensions overview, and a guide for creating extensions with React. Find them in the HubSpot developer docs. 4. Use the developer projects framework migration guide. HubSpot's official guide for migrating a public app to the developer projects framework is available now. Start here if you maintain a custom or public app. 5. Subscribe to the Developer Changelog. HubSpot has committed to publishing additional migration resources as the sunset date approaches. Subscribe so you don't miss them. 6. Build and test your App Card replacements. Don't wait for November 2025 migration guides. Use the existing beta documentation to begin rebuilding your Classic CRM Cards as App Cards in a sandbox environment. ## What It Touches in Your HubSpot Strategy This change isn't just a developer housekeeping item. It ripples into how your CRM records look and behave for every human in your portal. If your sales team depends on sidebar cards to see data from tools like Salesforce, Zendesk, Stripe, or a custom internal app, those cards need to be rebuilt. If a card breaks on November 1, 2026, that's a gap in context at the worst possible moment in a deal or service conversation. Here's what this update touches across your stack: - CRM records (contacts, companies, deals, tickets, custom objects): any sidebar card displayed on these record types could be affected. - Third-party Marketplace integrations: any app you've connected that uses Classic CRM Cards to surface data inside HubSpot will need to migrate or you'll lose that visibility. - Custom internal apps built by your dev team: if your RevOps or engineering team built a private app using the CRM Extensions API, that app needs to be rebuilt using the developer projects framework. - Portal UI customization strategy: this is a good forcing function to rethink what data actually belongs in your CRM record view, and to design App Cards that are genuinely useful rather than rebuilding clutter. > **Key takeaway:** Every third-party Marketplace app you use that shows a sidebar card in HubSpot could break on November 1, 2026 if its vendor hasn't migrated. Audit your connected apps now and ask vendors for a migration commitment in writing. If you're building a modern HubSpot setup, this is also a moment to revisit how your portal surfaces data to the humans using it every day. App Cards support richer interactions, like buttons, dropdowns, and form inputs inside the card itself. That's a meaningful upgrade in usability. This shift also fits into HubSpot's broader move toward a more programmable, agentic platform. If you haven't thought about where HubSpot's platform is heading, our deep dive on [the HubSpot agentic platform](https://www.sidekickstrategies.com/blog/hubspot-agentic-platform) gives you the full picture. > **Key takeaway:** App Cards aren't just a technical upgrade. They're the foundation HubSpot is building its next decade of CRM customization on. Building on App Cards now means your customizations stay supported, not sunset. ## Who Should Care Most Not every HubSpot portal will feel this equally. Here's who needs to act and who can watch from a distance. **Act now:** - HubSpot app developers and ISVs who maintain public or private apps that use Classic CRM Cards. The June 16, 2025 deadline for new submissions is close. - RevOps leaders at companies running complex portals with multiple integrations. You need to know what breaks on November 1, 2026 before it breaks. - Operations Hub users who've built custom sidebar experiences using the CRM Extensions API. Your builds need to move to the developer projects framework. **Monitor and plan:** - Marketing and sales ops teams using off-the-shelf Marketplace integrations. You're not writing code, but you should confirm your vendors have a migration plan. - Smaller portals with no custom apps or sidebar integrations. This change likely doesn't affect you today, but it's good context for future app decisions. ## George's Take We've seen this pattern many times across portals. A team builds something custom, it works fine for a couple of years, and then a platform shift creates a scramble. The humans running these portals aren't usually the ones who built the integrations. They just know something stopped working. That's why this update deserves attention now, not in October 2026. The window to audit, plan, and migrate without stress is open today. When we work through portal audits with clients, one of the first things we look at is what's in that right sidebar and whether it's actually serving the humans who open those records every day. This sunset is a forcing function to do that audit properly. > The worst time to discover a broken integration is during a live sales call. Audit your Classic CRM Cards today so your team never has to find out the hard way. > > _George B. Thomas_ If you're thinking about how HubSpot's tooling is evolving in ways that affect what humans see and experience in the CRM, it's also worth reading about [the Customer Agent Tester update](https://www.sidekickstrategies.com/hubspot-updates/hubspot-customer-agent-tester-every-configuration-page), which shows how HubSpot is pushing richer, more interactive surfaces across the board. If your portal uses any Classic CRM Cards and you're not sure where to start, let's talk. Our team has helped hundreds of portals through transitions like this. We'll audit what you have, map out the migration, and make sure nothing breaks when the deadline hits. ## Frequently Asked Questions ### What are Classic CRM Cards in HubSpot? Classic CRM Cards are static sidebar components built with the CRM Extensions API. They've been used for over a decade to display third-party data inside HubSpot CRM records. They're limited to the right sidebar, support only a few standard objects, and don't support dynamic interactions. HubSpot is replacing them with React-based App Cards. ### When will Classic CRM Cards stop working in HubSpot? Classic CRM Cards will stop working entirely on October 31, 2026. Starting June 16, 2025, you can no longer add new Classic CRM Cards to any HubSpot UI, and new Marketplace apps can't include them. Existing apps using Classic CRM Cards continue working until the October 31, 2026 hard deadline. ### What are HubSpot App Cards and how are they different? App Cards are built with React and powered by HubSpot's UI Extensions framework. Unlike Classic CRM Cards, they support dynamic interactions such as buttons, inputs, and dropdowns inside the card. They work across a wider range of CRM objects and aren't limited to the right sidebar, offering more flexibility for developers and richer experiences for users. ### Do I need to do anything if I only use Marketplace apps, not custom-built ones? Yes, you should still act. If any Marketplace apps you've connected use Classic CRM Cards to display data in your CRM sidebar, those cards will break on November 1, 2026 if the vendor hasn't migrated. Contact your app vendors now to confirm they have a migration plan and timeline in place before the sunset date. ### Where can I find resources to migrate Classic CRM Cards to App Cards? HubSpot has published beta documentation including a UI customization overview, a UI Extensions overview, a guide for creating extensions with React, and a migration guide for moving public apps to the developer projects framework. Full migration support resources are expected from HubSpot in November 2025. Subscribe to the Developer Changelog to stay updated. ### Will HubSpot notify me before Classic CRM Cards are shut down? HubSpot has committed to publishing migration resources through the Developer Changelog as the October 31, 2026 deadline approaches. They also have active channels including Developer Forums and a dedicated Slack channel for questions. Subscribe to the changelog and monitor those channels, but don't rely solely on notifications to drive your migration planning. ## Key facts - **Format:** HubSpot Update - **Published:** November 9, 2026 --- Source: https://www.sidekickstrategies.com/hubspot-updates/hubspot-classic-crm-cards-sunset-app-cards-migration Sidekick Strategies ยท HubSpot consulting and content operations