Best Retention &
CRO Agencies 2026
Affinsy's opinionated ranking of retention, email/SMS lifecycle and CRO agencies for e-commerce brands across the US, UK and DACH. We researched the field ourselves and scored what can be publicly verified, with a deliberate bias: demonstrated data work, not marketing claims. Rank position is never purchasable.
45 agencies · Updated July 15, 2026
How agencies are scored
Every agency is scored 0-100 across five pillars from publicly verifiable evidence collected in July 2026. Evidence is weighted by tier: independently verified beats self-published, self-published beats claimed. The weighting is ours and deliberately favors data-driven operators; we publish the full rubric so you can disagree with it.
The Data Sophistication pillar is scored from public claims until verified. Verification means showing the data work behind the listing: the fastest route is one free Affinsy analysis on a client store, but any credible evidence counts. Verified listings carry the ✓ Verified Data-Driven badge from the next monthly edition.
Proven results
Quantified case studies: email revenue share, LTV, CVR, repeat rate. Volume and standout bonuses on top of an evidence base score.
Specialization
Klaviyo partner tier (Elite > Master Platinum > Master Gold > Platinum > Partner) or CRO-platform credentials. Self-claimed expertise scores low.
Data sophistication
Segmentation / RFM, predictive LTV, structured testing program, attribution, CDP. Scored from each agency's public claims until verified with real evidence.
Reputation
Third-party review volume and rating, industry awards, community footprint.
Track record
Years operating and client volume in e-commerce retention or CRO.
Excluded during sourcing: platform and tool vendors (Ebbo, ELAINE, Salesfire), absorbed agencies (Electriq), experimentation firms without an e-commerce-primary practice (Conversion.com, Cro Metrics, Speero, Daydot, Creative CX), generalists (WAUMEDIA, e-dialog), and agencies whose claims could not be verified (REO).
Earn the Verified Data-Driven badge
Show the data work behind your listing: run a free analysis on one client store, or submit equivalent evidence. The badge lands in the next monthly edition.
Verification is free · Rank position is never purchasable