Session ReplayJan 8, 2026
[All updates]

Session Replay Amplitude Session Matching

Lew Gordon
Lew Gordon

Description: • Session Replay matches replays to Amplitude data to provide a complete view of the user journey. This matching links device and session information from Session Replay to Amplitude sessions. Previously, matching was limited to the Amplitude session_id, which meant customers using custom session definitions weren’t fully supported. Session Replay now offers multiple session matching options, giving customers flexibility while keeping setup lightweight.

• Session matching options:

  1. Match Amplitude sessions (recommended) - Fully aligns Session Replay with Amplitude sessions, including custom session definitions, for the most accurate end-to-end view of the user journey. Note: If customers use a custom session ID in Amplitude, the Session Replay SDK must send the same session ID value so sessions can be matched correctly.
  2. Time-based event matching - Builds sessions using 30- or 60-minute time windows based on event activity. Designed for customers who can’t send a session ID from their frontend due to technical or architectural constraints. While slightly less precise than true session matching, it still delivers a reliable and useful journey view.
  3. Legacy matching - Matches based on the Amplitude session_id, even if it doesn’t align with custom session definitions. This option exists for backward compatibility and requires no changes.

Why: Customers define sessions in different ways. Some rely on custom session logic, while others can’t use the Amplitude session_id due to complex data pipelines or technical limitations. These options remove common blockers to Session Replay adoption while still guiding customers toward the most accurate setup. Matching Amplitude sessions is strongly recommended whenever possible.

FAQs: • Which option should customers use? Match Amplitude sessions whenever possible. This includes custom session definitions, as long as the same session ID is sent to both Amplitude and Session Replay. • Does this require re-instrumentation? Usually no. For customers using custom sessions, the only requirement is ensuring the Session Replay SDK sends the same session ID value already used in Amplitude. • Can customers change this later? Yes. Session matching is quick to change and fully reversible. • Does this affect historical data? No data is lost. The change impacts how replays are matched and viewed going forward. • Is legacy matching being deprecated? No. It remains supported, though newer options are recommended for most customers.

Notes: • Session matching changes are fast and reversible • Only configurable at the org level on the Session Replay settings page. • No customer-facing performance or pricing impact • Customer docs specify how to pass a matching session ID via the SDK • Public docs: https://amplitude.com/docs/session-replay/session-matching#time-based-event-matching

Available in EUDC: Yes

When: Live now