The 10 best ecommerce data consultancies in 2026

If you sell through Shopify, Amazon, or TikTok Shop and your channel, finance, and marketing numbers disagree, you probably need a data partner rather than another dashboard app. This list covers ten firms that build warehouses, attribution, and margin and retention reporting for online brands.

Greyfield Data builds that reporting layer in Snowflake, dbt, and Sigma. See ecommerce data warehouses and reporting, or put a number on retention first with the retention value calculator.

Which list do you need? This one is for brands that sell mostly online: DTC sites, subscriptions, and marketplaces. If a large share of your revenue comes through retailers, distributors, or wholesale accounts, and you need POS, syndicated data such as SPINS, Nielsen, or Circana, and trade spend reporting, read the 10 best consumer brand analytics consultancies instead.

Disclosure. Greyfield Data wrote this list and is on it, listed first. The other nine are in no particular order. We picked firms that publicly describe ecommerce or retail data work, and every detail about them comes from their own website, linked in each section. We have no commercial relationship with any of them. If something is out of date, email us and we will fix it.

Key takeaways

• Ecommerce data consultancies fall into three groups: warehouse and modeling firms, measurement and tracking specialists, and growth marketing firms with a data practice.
• Pick the group before the firm. A tracking specialist will not build margin models, and a warehouse consultancy will not fix a broken pixel.
• For contribution margin and retention by channel, you need a warehouse with explicit rules for refunds, fees, and dates. Ask every firm to show how they define those.
• Small brands often do better with a packaged tool first. A warehouse earns its cost when you need sources or margin logic the tool does not support. The /compare pages show both sides.
• Ask who will run the system after launch: the firm or your own team.

Download the full-size list (PNG)

How did we pick these firms?

We looked for consulting firms that a DTC or marketplace brand could hire today for data work, and kept those that met most of these criteria:

• Ecommerce focus. The firm's own site names ecommerce, retail, Shopify, or DTC work, not just "all industries".
• Public evidence. Case studies, a named industry page, or a vendor partner listing on its site.
• Size fit. A mix from small specialists to larger agencies, so you can match the firm to your team.
• Transparency. The site says what the firm does, which tools it uses, and how engagements work.

We left out software and product companies, including those that sell services alongside their product, and firms we could not verify from their own site. We did not use reviews, rankings, or awards from third parties.

How do the 10 firms compare?

#	Firm	Best for	Type	HQ	Notable (from its site)
1	Greyfield Data	Snowflake, dbt, and Sigma reporting for Shopify, Amazon, and TikTok Shop	Independent consultancy	Serves the US	Ecommerce case studies
2	Brooklyn Data	dbt-first warehouse builds	Consultancy, part of Velir	Not listed	Platinum dbt Partner; Sigma Certified Delivery Partner
3	Rittman Analytics	Google Cloud, dbt, and Looker builds	Boutique consultancy	Brighton, UK	Ecommerce & Retail practice; BARK case study
4	Tasman Analytics	European scale-ups that want the work handed over	Consultancy	Not listed	Working with companies across Europe since 2017
5	Brainforge	Larger brands joining DTC, wholesale, and retail metrics	Data and AI services firm	Dallas, TX	CPG and ecommerce industry page with case studies
6	i-spark	European DTC and multi-market webshops	Data and AI consultancy	Groningen, Netherlands	E-commerce & D2C practice; Snowflake, dbt, Google Cloud
7	Measurelab	GA4, server-side tracking, BigQuery	Consultancy	UK	Google Cloud Select Services Partner
8	InfoTrust	Google Marketing Platform measurement	Analytics consultancy	Not listed	Retail & eCommerce and CPG & Multi-Brand practices
9	Vision Labs	Tracking and BigQuery reporting for growing online brands	Data consultancy	Not listed	Bobbie case study: Shopify and ad data in BigQuery
10	Winston Francois	Attribution and cohort LTV with growth marketing	Growth marketing firm	Not listed	Data, reporting and analytics practice for DTC

"Not listed" means the firm's site did not state it when we checked in November 2026.

1. Greyfield Data

Greyfield Data is an independent consultancy led by Linus Tse. It builds ecommerce data warehouses and reporting in Snowflake, dbt, and Sigma, joining Shopify, Amazon, TikTok Shop, ad platforms, inventory, and finance data so revenue, margin, and retention agree across teams.

• Best for: online brands whose channel numbers disagree and who want one set of definitions for orders, refunds, fees, and margin.
• Why it stands out:
  • You work directly with the senior person doing the build.
  • Results in published case studies: a multi-brand ecommerce portfolio answers cross-brand questions in minutes instead of two weeks, and a DTC apparel brand went from weekly pipeline failures to rare ones.
  • Platform neutral: no software to resell, so the stack is picked for the brand. It is all in the free ecommerce data stack white paper.
  • Free tools for brands: the ecommerce data stack quiz, retention value calculator, and a unified customer timeline demo.
• Link: greyfielddata.com/ecommerce

2. Brooklyn Data

Brooklyn Data is a data consultancy offering strategy, engineering, analytics, and data science on the modern data stack. Its site describes it as "a Platinum dbt Partner and the 2023 Training Partner of the Year", lists Snowflake as a partner, and says it is a Sigma Certified Delivery Partner.

• Best for: brands that want a dbt-centered warehouse built to a high engineering standard.
• Worth knowing: Brooklyn Data is part of Velir, a digital agency, and lists Ecommerce & Retail among its industries. If Sigma is your BI tool, see also the best Sigma consulting firms.
• Link: brooklyndata.co

3. Rittman Analytics

Rittman Analytics describes itself as a "Boutique data consultancy building modern data platforms and AI-ready analytics". It specializes in Google Cloud and lists partnerships with dbt Labs, Fivetran, Cube, and others.

• Best for: brands on BigQuery and Looker that want an ecommerce warehouse and marketing analytics.
• Worth knowing: its homepage features an Ecommerce & Retail industry page, a BARK case study, and an "RA eCommerce Warehouse" resource. It is based in Brighton, UK.
• Link: rittmananalytics.com

4. Tasman Analytics

Tasman Analytics builds data capabilities and then hands them over to the client's team. Its services cover data strategy, infrastructure and migrations, analytics and reporting, and advanced analytics.

• Best for: European scale-ups and subscription businesses that want an internal team running the stack after the project.
• Worth knowing: the site says it is "tool-agnostic" and has worked with companies across Europe since 2017, according to its about page. Its homepage includes an ecommerce story for Eve Sleep.
• Link: tasman.ai

5. Brainforge

Brainforge is a data and AI services firm. Its CPG and ecommerce page says "We put DTC, wholesale, and retail on one metric contract your leadership can trust" and covers LTV to CAC and marketing efficiency across channels, with a data lake and attribution model the client controls.

• Best for: larger online brands that also sell wholesale or in retail and want one set of metrics across channels.
• Worth knowing: the page links case studies including one view of every marketing campaign, and its site gives Dallas, TX as its location. It is also on the consumer brand list.
• Link: brainforge.ai

6. i-spark

i-spark is a data and AI consultancy from Groningen in the north of the Netherlands. Its e-commerce and D2C page covers true profit per product once returns and ad spend are in, acquisition channels that bring back repeat buyers, multi-market reporting, and subscription reorder forecasting.

• Best for: European DTC brands and multi-market webshops that want order, stock, customer, and marketing data on one shared model.
• Worth knowing: it works on Snowflake, dbt, and Google Cloud, with reporting in Power BI, Looker, and Looker Studio, and offers a "Data-Team-as-a-Service" that scales up or down. Its WWL case study is in Dutch.
• Link: i-spark.nl

7. Measurelab

Measurelab is a UK-based marketing data and analytics consultancy working on Google Cloud and the Google Marketing Platform. Its work spans tracking and consent (GA4, Google Tag Manager, server-side tracking), BigQuery pipelines, and marketing analytics.

• Best for: brands whose first problem is tracking: missing conversions, consent, and GA4 data you cannot trust.
• Worth knowing: it lists Google Cloud Select Services Partner status and a Marketing Analytics Services Specialization, and works with organizations "From financial services to retail".
• Link: measurelab.co.uk

8. InfoTrust

InfoTrust is a digital analytics consultancy focused on data collection, privacy, and media measurement. It lists Retail & eCommerce and CPG & Multi-Brand among its industries.

• Best for: larger retail and ecommerce brands on Google Analytics 360 and the Google Marketing Platform.
• Worth knowing: its retail and ecommerce page mentions custom multi-touch attribution models and predictive revenue forecasting. It is a Google Marketing Platform Certified Sales Partner and lists four offices.
• Link: infotrust.com

9. Vision Labs

Vision Labs describes itself as "a data consultancy" that handles data systems and technical work for growing companies. Its services include GA4, Google Tag Manager, and Looker Studio implementation, data warehouse consulting with BigQuery, and a fractional data team, and it lists ecommerce among the businesses it works with.

• Best for: online brands that need tracking fixed and paid media and Shopify data reporting in BigQuery, without hiring a data team.
• Worth knowing: its Bobbie case study covers a DTC infant formula subscription brand, bringing Shopify and five ad platforms into BigQuery with Looker Studio dashboards.
• Link: visionlabs.com

10. Winston Francois

Winston Francois is a growth marketing firm with a data, reporting, and analytics practice for DTC and ecommerce brands. Its data page covers measurement audits, attribution architecture, customer data infrastructure, and cohort LTV by acquisition channel.

• Best for: DTC brands that want analytics planned alongside growth marketing rather than as a separate project.
• Worth knowing: the page describes engagements in 90-day build cycles and asks for a warehouse, or willingness to set one up, plus an internal counterpart.
• Link: winstonfrancois.com

How do you choose an ecommerce data consultancy?

Start with the problem, not the firm. If conversions are missing, you need tracking help. If channel revenue and margin disagree, you need a warehouse and models. If you want answers fast and your definitions are standard, a packaged tool may be enough; the ecommerce data stack map shows where each option sits.

Questions to ask

• How will you define an order, a refund, and a customer across Shopify, Amazon, and TikTok Shop? Our guide on avoiding double-counted orders shows why this matters.
• Which date does a refund belong to, and which fees are in contribution margin?
• Who owns the code and the warehouse account at the end?
• Who runs it after launch, and what does monitoring look like?
• Can you show a past model or case study for a brand our size?

Red flags

• A dashboard demo before anyone has asked about your definitions.
• Attribution promised as a single "true" number.
• No plan for tests or reconciliation against finance.
• The contract does not say who owns the code and the warehouse account if you leave.

Frequently asked questions

What does an ecommerce data consultancy do?

It connects your storefronts, marketplaces, ad platforms, and finance tools into one place, then defines revenue, margin, and retention once so every report agrees. Some firms focus on tracking, others on the warehouse and models.

Do I need a data warehouse or a packaged analytics app?

A packaged app is often enough for a single Shopify store with standard definitions. A warehouse earns its cost when you sell in several channels, need your own fee and margin logic, or want one model shared by several tools. The comparison pages go tool by tool.

Should I hire a Snowflake specialist or an ecommerce specialist?

Ideally both in one firm. A warehouse specialist without ecommerce experience will learn your refund and fee rules on your budget. If Snowflake is already your platform, see the best Snowflake consulting firms.

How is this list different from the consumer brand list?

This list is for brands selling mostly online. The consumer brand list covers brands that also sell through retailers and wholesale, where POS, syndicated data, and trade spend matter.

What to do next

If your Shopify, Amazon, and finance numbers do not agree, try the ecommerce analytics tool quiz to see whether a packaged tool or a warehouse fits, or book a call with Linus to talk through your sources.