How agencies manage analytics across multiple Klaviyo accounts

You manage email marketing for 15 clients. Each one has their own Klaviyo account. To compare performance across clients you log into each account, export the data, paste it into a spreadsheet, and normalize the metrics by hand. Every week.

The problem

Klaviyo's MCP connector queries one account at a time. That is fine for a single brand, but an agency's questions are all cross-account ones. Which client has the best open rates? Which flows are underperforming against your portfolio average? What could your worst-performing client copy from your best one?

None of those can be answered without exporting from every account and stitching it together by hand. That is not analytics, it is data entry.

The setup

1. All your Klaviyo accounts → Airbyte or Fivetran
2. Airbyte or Fivetran → Snowflake (or BigQuery)
3. Snowflake → Contextflo
4. Contextflo → Claude

The ETL tool syncs every Klaviyo account into one warehouse, each client in its own schema. Contextflo connects to the warehouse and generates context for every table, so Claude knows what the columns mean rather than guessing from names.

What you can ask once it is connected

Which client has the highest email open rate this month, and how does it compare to the portfolio average?

Show me abandoned cart flow conversion rates across all clients, ranked worst to best.

What subject line patterns are working best across the portfolio this quarter?

Client X's welcome flow is underperforming. Show me how Client Y's compares so I can apply what's working.

No logging in and out. No spreadsheet. The last question is the one that actually matters, and it is the one you currently cannot ask at all.

Keeping client data separate

Putting fifteen clients in one warehouse raises an obvious question, and it is worth answering before someone else asks it. Each client lands in its own schema, and access is controlled per data source, so a strategist who works on three accounts can be given those three and nothing else.

That matters for two reasons. Client contracts often say their data will not be commingled or exposed to third parties, and you want a straight answer when a client asks. And internally, portfolio-level questions should be something you run deliberately, not something any account manager stumbles into.

Why this matters for agencies

Your advantage as an agency is the pattern recognition you build across clients. You can only build it if you can see across clients. While the data sits in fifteen separate Klaviyo logins, every insight stays stuck in the account it came from, and the only person who notices a pattern is whoever happens to work on both accounts.

Once it is in one place, new strategists ramp on what already works instead of rediscovering it, client reports take minutes, and you can show a prospect portfolio-wide numbers rather than an anecdote.