Every official Klaviyo change that affects advertisers (Klaviyo email, SMS, flows, forms, Composer and the Klaviyo API), newest first. Each one links to its source. Last logged Oct 15, 2026.
What to do: Ask the vendors behind custom Klaviyo integrations which revision they pin, and get anything on 2024 revisions upgraded.
Source: Klaviyo API changelog ↗
What to do: If an app or script creates Klaviyo campaigns through the API, have its owner test against 2026-10-15 before upgrading the revision header.
Source: Klaviyo API changelog ↗
What to do: If checkout SMS opt-in is low, test the new block, and confirm consent language meets TCPA rules.
Source: Klaviyo Help Center ↗
What to do: If you keep subscription or loyalty data outside Klaviyo, model one object and try it in a flow.
Source: Klaviyo Help Center ↗
What to do: If you mail EU subscribers, add the consent field to your forms and check how untracked profiles affect engagement segments.
Source: Klaviyo Help Center ↗
What to do: Convert legacy coded templates so the team can edit them without a developer.
Source: Klaviyo Help Center ↗
What to do: Schedule a weekly flow audit in Composer and compare it with your own read.
Source: Klaviyo Help Center ↗
What to do: Before you rely on it, ask it for a number you already trust, like repeat-purchase rate or last month's flow revenue, and check that its revenue definition (gross or net, refunds in or out) matches your reporting.
Source: Klaviyo Community ↗
What to do: If you use Klaviyo Social, add social revenue to your weekly channel report.
Source: Klaviyo Help Center ↗
What to do: Turn it on if customers use your app on several devices.
Source: Klaviyo What's New ↗
What to do: Try a post-purchase preference or zero-party data form triggered from your existing flows.
Source: Klaviyo Help Center ↗
What to do: Turn on quiet hours for SMS campaigns before BFCM. Late-night sends across time zones are a common TCPA risk.
Source: Klaviyo Help Center ↗
What to do: Use it for the monthly owned-channel review instead of stitching exports.
Source: Klaviyo Help Center ↗
What to do: Decide on a tracking policy for EU recipients, and note that click-based segments and reports will thin out for untracked profiles.
Source: Klaviyo Help Center ↗
What to do: If you sell very different products, like subscriptions and one-offs, split RFM by line.
Source: Klaviyo Help Center ↗
What to do: Set it up. More identified visitors means more browse and cart abandonment triggers.
Source: Klaviyo Help Center ↗
What to do: Request the beta if SMS abandonment flows are a big revenue line, and A/B test against your current copy.
Source: Klaviyo What's New ↗
What to do: No action needed. Peak-day flow delays should shrink.
Source: Klaviyo What's New ↗
What to do: If you connect an agent, start with a read-only key, and review API analytics to see what it called.
Source: Klaviyo MCP server docs ↗
What to do: Re-enable send-time optimization on campaigns where you'd turned it off to run tests.
Source: Klaviyo Help Center ↗
What to do: Use minute-level batching for big drops that tend to crash your site or checkout.
Source: Klaviyo Help Center ↗
What to do: Use the backfill flag for migrations so you don't re-fire flows, and have SMS integrations updated before adopting the revision.
Source: Klaviyo API changelog ↗
Backfilled to Jul 15, 2026. Spot a Klaviyo change we missed? It goes into the next review run.