# Best AI Agencies for Retainer Work in Berlin

> 7 agencies. Top-ranked: ontolux, Hybrid Heroes, Contiamo.

Canonical page: https://www.aiagencies.eu/for/retainer/berlin
Generated: 2026-09-28 · Curated by Gabor Kiss · No paid placements — inclusion, score, and rank are never sold.

## Ranked roster
1. **ontolux** — Berlin, Germany · rate not published · team 10-49 · services: AI Development, AI Consulting, Generative AI · 11 documented client engagements with source URLs · reviewed 2026-09-24 · https://www.aiagencies.eu/agency/ontolux
2. **Hybrid Heroes** — Berlin, Germany · €85-130/hr (directory-listed) · team 10-49 · founded 2015 · services: AI Consulting, AI Development, Generative AI, AI Agents · 7 documented client engagements with source URLs · reviewed 2026-08-05 · https://www.aiagencies.eu/agency/hybrid-heroes
3. **Contiamo** — Berlin, Germany · rate not published · team 10-49 · founded 2012 · services: AI Consulting, AI Development, Generative AI · 6 documented client engagements with source URLs · reviewed 2026-09-24 · https://www.aiagencies.eu/agency/contiamo
4. **wegewerk** — Berlin, Germany · rate not published · services: AI Consulting, AI Development, Generative AI · 3 documented client engagements with source URLs · reviewed 2026-08-05 · https://www.aiagencies.eu/agency/wegewerk
5. **Birds on Mars** — Berlin, Germany · rate not published · founded 2017 · services: AI Consulting, AI Development · 3 documented client engagements with source URLs · reviewed 2026-08-04 · https://www.aiagencies.eu/agency/birds-on-mars
6. **punktum digital** — Berlin, Germany · €45-85/hr (directory-listed) · team 2-9 · founded 2022 · services: AI Development, AI Consulting · 3 documented client engagements with source URLs · reviewed 2026-08-04 · https://www.aiagencies.eu/agency/punktum-digital-gmbh
7. **Limebit** — Berlin, Germany · rate not published · team 2-9 · founded 2016 · services: AI Development, AI Consulting · 2 documented client engagements with source URLs · reviewed 2026-09-09 · https://www.aiagencies.eu/agency/limebit


## About this market
Retainer work in Berlin shows up mostly as long client tenure, and the dates on this page are the evidence. ontolux describes its work as running from first analysis to operation, and its client notes back that up: Creditreform's company-profile search since 2009, PMG Presse-Monitor's entity tagging across 170,000+ articles a day since 2012, ZDF's CMS tagging service since 2021. Limebit's machine-learning validation of electronic prescriptions ran in production for statutory health insurers from 2022 to 2025. Contiamo's GPT-4o chatbot at Stadtwerke Bonn has answered tariff questions for over a year, and the firm describes supporting BRAX for several years. Birds on Mars names stable operation and long-term maintenance of production AI systems as a service; wegewerk has kept foodwatch's platform running since 2015, though that is web upkeep rather than AI.

For a Berlin buyer the sorting question is what the retainer pays for once the system is live: monitoring and retraining a model, or keeping an application and its integrations running. Hybrid Heroes describes app operations that often run for years and punktum digital offers long-haul support, which is product upkeep with a model inside. The text-analysis and prescription systems depend on quality holding over years, yet the published references report history and method rather than quality figures, and the curator notes ask for them. Ask each candidate what a month of the retainer produced for an existing client, and what you would hold if you ended it: code, pipelines, documentation.

## Questions buyers ask

### How many AI agencies work with retainer in Berlin?
7 agencies in our directory combine verified retainer client evidence with a Berlin base. The current top-ranked are ontolux, Hybrid Heroes, Contiamo — ordered by depth of documented client evidence, then our editorial scoring (portfolio quality, credibility, completeness); placement is never paid.

### How much does an AI agency cost in Berlin?
Published rates across this page's agencies run €45–130 per hour (median ~€86). Project totals depend on scope — the rate index at /rates breaks the computed bands down by region, country and team size.

### How is the retainer model verified?
Every agency here documents retainer work on its own site or in a published case study, describing the engagement structure rather than a service-list claim. We never infer the model from portfolio tone, so this list only contains agencies that operate retainer engagements deliberately.

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Source: AIAgencies.eu — the curated register of European AI agencies. Rate provenance: "agency-confirmed" = disclosed via submission or claimed profile; "directory-listed" = Clutch or two agreeing B2B directories (lone unverified sources are never written). Full method: https://www.aiagencies.eu/methodology · Rate index: https://www.aiagencies.eu/rates