# Best AI Marketing Agencies for Retainer Work

> 7 agencies. Top-ranked: OstraconAI, Redkiwi, Found.

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

## Ranked roster
1. **OstraconAI** — Helsinki, Finland · €250-400/hr (agency-confirmed) · team 10-49 · founded 2024 · services: AI Consulting, AI Marketing, AI Automation · 11 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/ostraconai
2. **Redkiwi** — Rotterdam, Netherlands · rate not published · team 10-49 · services: Generative AI, AI Marketing, AI SEO · 7 documented client engagements with source URLs · reviewed 2026-09-24 · https://www.aiagencies.eu/agency/redkiwi
3. **Found** — London, United Kingdom · €85-130/hr (directory-listed) · team 50-249 · founded 2005 · services: AI SEO, AI Marketing, AI Automation · 8 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/found
4. **NOVOS** — London, United Kingdom · €130-170/hr (directory-listed) · team 10-49 · founded 2018 · services: AI SEO, AI Marketing · 5 documented client engagements with source URLs · reviewed 2026-09-23 · https://www.aiagencies.eu/agency/novos
5. **Ekimetrics** — London, United Kingdom · rate not published · team 50-249 · founded 2006 · services: AI Consulting, AI Marketing, Generative AI · 8 documented client engagements with source URLs · reviewed 2026-09-07 · https://www.aiagencies.eu/agency/ekimetrics
6. **Inbold** — Oslo, Norway · €85-130/hr (directory-listed) · team 50-249 · founded 2005 · services: AI Marketing, Generative AI, AI Consulting · 3 documented client engagements with source URLs · reviewed 2026-09-09 · https://www.aiagencies.eu/agency/inbold
7. **wukonig.com** — Graz, Austria · rate not published · founded 1999 · services: AI SEO, AI Consulting, AI Marketing · 3 documented client engagements with source URLs · reviewed 2026-09-09 · https://www.aiagencies.eu/agency/wukonig


## About this market
Marketing retainers here range from tools the client's own team ends up running to campaigns produced on the client's behalf. OstraconAI documents the first kind with numbers: the Gosta Labs oncologist outreach retainer, described as ongoing, sent 3,930 messages for 198 replies and 62 opportunities; Woodly's UK market-entry outbound on Clay, Apollo and Instantly produced more than 120 qualified leads in five months; Olo-apteekki's banner generator took per-set production from 20 to 30 minutes to near-instant. Redkiwi's client AI sits inside web and campaign delivery, the Esbjaerg Vodka image library in place of a shoot. NOVOS's Osprey program moved share of AI answers to 72.6%. Ekimetrics retains for marketing-mix modeling, with Eurostar the one named case study. Inbold has produced Ambu's instructions-for-use since 2016 across 27 languages, a retainer but not an AI one. wukonig.com's named work is a prompting program for TCM International's sales team.

The sorting question for a marketing retainer is what your team can do the day it ends. OstraconAI trains staff and builds on platforms the client can hold, though the curator asks who owns the workflows and accounts afterward and which headline figures were measured rather than forecast. NOVOS and wukonig.com sell continuity by design, a program that stops moving when it stops, which is fine if the target is independently measurable. Inbold and Redkiwi are production capacity, priced on output. Ask each which figures on their case pages were measured after launch, and which are quotes.

## Questions buyers ask

### How many AI agencies work with retainer on ai marketing?
7 agencies in our directory combine verified retainer client evidence with documented AI Marketing work. The current top-ranked are OstraconAI, Redkiwi, Found — 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 for ai marketing?
Published rates across this page's agencies run €85–400 per hour (median ~€129). 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