The Ecomm Analyst

Agency attribution is a different problem from in-house attribution, and most roundups in this category do not acknowledge that. When you run one store, you are optimizing for depth. When you run fifteen client accounts, you are optimizing for something else entirely: how fast you can onboard a new store, whether the reporting is defensible in a client meeting, and whether your tooling cost scales linearly with your client count or eats your margin as you grow.

That last one is what actually kills agencies. Per-seat and per-source pricing models were designed for in-house teams and they punish anyone managing a portfolio. Here are five options that hold up across multiple stores, with July 2026 pricing.

1. Windsor.ai

The best value on this list for an agency, mostly because of what it refuses to charge for. Every plan includes all 325 or so connectors, all destinations, and unlimited users. No premium connector upcharges, no per-seat fees, no paying extra to send data somewhere.

Pricing runs Basic at $19 a month, Standard at $99, Plus at $249, and Professional at $499, billed annually, with a free forever tier and custom Enterprise pricing. Account limits are what you watch: Basic covers 75 accounts, Plus 200, Professional 500. For an agency, that account allowance is the real constraint rather than the connector count.

The cost lever is Monthly Active Rows, with extra volume at roughly $20 per million. Agencies pulling long lookback windows across many accounts hit this faster than expected, so model it before you commit annually. Windsor is also a pipeline product rather than a client-facing dashboard, so you are pairing it with Looker Studio or similar. That is fine, and arguably better than a closed reporting tool, but it is work. More in Windsor.ai alternatives.

2. ThoughtMetric

ThoughtMetric, which sponsors this blog, runs a formal agency partner program, and it is one of the few attribution-first tools in this price band that treats multi-store management as a first-class case rather than an afterthought. Reviewers on G2 and Capterra skew heavily toward small business and agency users, and the recurring theme in those reviews is speed of launch across a client portfolio.

Pricing starts at $99 a month per store for 50,000 pageviews and scales on pageviews rather than client revenue, with all features at every tier. For an agency, per-store pageview pricing is usually kinder than GMV-based models, since your smaller clients stay genuinely cheap instead of paying a floor price built for larger brands.

It supports both Shopify and WooCommerce natively, which matters more for agencies than for single-brand operators, since your client base rarely standardizes on one platform. The honest limitation is the same as everywhere else: this is attribution and channel reporting, not media mix modeling, and it is not a white-labeled client reporting suite. If your deliverable is a branded monthly PDF, you are pairing it with something else. The ThoughtMetric vs Polar Analytics comparison covers the reporting depth tradeoff.

3. Supermetrics

The incumbent, and still the most complete connector library in the category. If you need a data source that exists, Supermetrics almost certainly supports it, and the Sheets and Looker Studio integrations are what a lot of agency reporting workflows were built on.

The pricing model is the problem for agencies. Supermetrics charges per user, starting around €29 to €37 per user per month at the Starter tier and jumping to roughly €159 to €189 per user per month above that, with destinations, premium connectors, and warehouse access frequently sitting behind higher tiers or paid add-ons. For a ten-person agency, that per-seat structure compounds fast.

Users also report unpredictable renewal increases and unclear fair-usage limits, which is a recurring theme in the reviews rather than an isolated complaint. It works, it is reliable, and you will pay for both. See Supermetrics alternatives.

4. Whatagraph

Built for the client-facing half of the job. If your problem is that reports look amateurish or take a strategist ten hours a month to assemble, Whatagraph solves that specific thing well, with white-labeled templates and drag-and-drop dashboards across roughly 55 native integrations.

There is a forever-free tier with 5 source credits, then paid plans starting around $229 a month for 20 credits and roughly $463 for the next tier up, with Enterprise quote-only. Note that Whatagraph restructured its pricing in mid-2026 and third-party sources disagree on current plan names, so verify directly before committing.

Two things to know. Pricing is credit-based on data sources rather than client count, so an agency with five clients using eight sources each burns through the entry tier immediately. And paid plans are annual billing only, with no monthly option, which is a meaningful commitment for a tool you have not stress-tested. There is also no SQL access and no raw export to a warehouse, so this is a reporting layer rather than a data foundation. More in Whatagraph alternatives.

5. Improvado

The enterprise option, and the right answer only for agencies past a certain size. Improvado handles the full pipeline with 500 or so connectors, a marketing data model, governance rules, and dedicated onboarding, which is genuinely different from a reporting tool that pulls APIs and draws charts.

Pricing is quote-only. Improvado’s own published guidance puts a mid-market agency managing 15 to 25 clients across 30 to 50 data sources in the range of $3,000 to $6,000 a month, which is a useful anchor even accounting for the source. Below roughly fifteen clients the math is difficult to justify.

The argument for it is that pipeline maintenance is a real cost you are already paying in analyst hours, just invisibly. If someone on your team spends fifteen hours a month babysitting connectors, that is not free. Whether it clears $3,000 a month is a question only your headcount math answers. See Improvado alternatives.

How I would actually stack these

Most agencies under twenty clients end up running two tools rather than one, because attribution and client reporting are different jobs and the products that claim to do both do neither especially well. A common shape is a per-store attribution tool plus a reporting layer, which lands somewhere under $500 a month all in for a mid-sized book.

Whatever you pick, run the cost math at double your current client count. Agency tooling decisions are sticky, migration is painful, and the pricing model you choose today is the one you will be arguing with in eighteen months. For the single-store version of this list, see best e-commerce attribution tools.