> For a complete page index, fetch https://docs.synthflow.ai/llms.txt. For full documentation content, fetch https://docs.synthflow.ai/llms-full.txt. # Voice Widget migration > What changes when Synthflow moves every existing Voice Widget to the upgraded design and real-time backend on September 16, 2026, and how to test the new embed before then. The [upgraded Voice Widget](/changelog/2026/6/30) design and faster real-time backend have been available since June 30, 2026. New widgets have used it by default since that date, and existing widgets have stayed on the old embed until their owner chose to upgrade. That opt-in period ends. On **September 16, 2026**, Synthflow moves every remaining Voice Widget to the new design and backend automatically. You do not need to do anything. The move happens on Synthflow's side, and the embed code already on your site keeps working. This page is here so you know what changes, and so you can verify the new widget on your own site ahead of the cutover if you want to. ## Who is affected You are affected if you have a [Voice Widget](/create-an-agent#voice-agent) agent that was created before June 30, 2026 and has not been upgraded since. Those widgets are still serving the old design and the old real-time backend. You are not affected if: * Your Voice Widget was created on or after June 30, 2026. It already runs the new design and backend. * You already copied the new embed code from **Deploy** into your site. That widget is migrated. * You only use [chat widgets](/launch-chat-agents#embeddable-chat-widget). This change covers Voice Widgets only. To check a widget, open the agent in the dashboard and go to the **Deploy** tab. If the embed code shown there differs from the snippet on your site, that widget is still on the old version and will be moved on September 16, 2026. ## What changes * **Visual design.** The widget uses the upgraded look introduced on June 30, 2026. * **Real-time backend.** Voice runs on the faster real-time backend, which lowers latency during the call. ## What stays the same * **Your embed code.** The snippet already on your page continues to load the widget. You do not need to redeploy your site for the migration to take effect. * **Agent behavior.** Prompts, [actions](/actions-overview), [knowledge bases](/knowledge-base), voice settings, and [call logs](/logs) are unchanged. The migration replaces the widget shell, not the agent behind it. * **Your agent configuration.** Nothing in the agent editor needs to be rebuilt or republished. ## Test before the cutover If you want to confirm the new widget behaves correctly on your own site before September 16, 2026, you can move a widget over yourself and watch it in your environment: 1. Open the agent in the Synthflow dashboard and select the **Deploy** tab. 2. Copy the new embed code. 3. Paste it into your site in place of the existing snippet. Use a staging environment first if you have one. 4. Load the page and start a call with the widget. Check that it renders correctly against your site's layout and styling, and that audio connects and the agent responds as expected. Upgrading a widget yourself cannot be reversed for that widget. Once you deploy the new embed code, that widget stays on the new design and backend. It will be moved on September 16, 2026 regardless, so upgrading early only changes the timing. If the widget looks wrong against your site's CSS, adjust your own page styling before the cutover date, or [contact support](https://synthflow.ai/contact) so the issue can be looked at while you still have the old embed as a reference. ## What happens on September 16, 2026 Every remaining Voice Widget is switched to the new design and backend. There is no downtime and no action required from you or your customers. Calls in progress at the moment of the switch are unaffected. After the cutover, the old widget design is no longer served, and there is no way to move a widget back to it. ## FAQ #### Do I need to update the embed code on my site? No. The migration happens on Synthflow's side and the snippet already on your page will load the new widget. Copying the new embed code from **Deploy** is only useful if you want to move a widget over early and test it. #### Can I opt out or stay on the old widget? No. The old design and backend are being retired on September 16, 2026, and every remaining widget is moved over on that date. #### Can I roll back after the migration? No. The change cannot be reversed, whether Synthflow moves the widget for you or you upgrade it yourself beforehand. #### Will my agent's prompt, actions, or knowledge base change? No. Only the widget shell and the real-time backend change. The agent configuration behind the widget is untouched. #### Does this affect chat widgets? No. This migration covers [Voice Widgets](/create-an-agent#voice-agent) only. The [embeddable chat widget](/launch-chat-agents#embeddable-chat-widget) is unchanged. #### How do I know which of my widgets are still on the old version? Open each Voice Widget agent and compare the embed code on the **Deploy** tab with the snippet deployed on your site. If they differ, that widget is still on the old version. #### Will there be downtime during the migration? No. Widgets stay available throughout, and calls in progress at the time of the switch are not interrupted.